• unlimited access with print and download
    $ 37 00
  • read full document, no print or download, expires after 72 hours
    $ 4 99
More info
Unlimited access including download and printing, plus availability for reading and annotating in your in your Udini library.
  • Access to this article in your Udini library for 72 hours from purchase.
  • The article will not be available for download or print.
  • Upgrade to the full version of this document at a reduced price.
  • Your trial access payment is credited when purchasing the full version.
Buy
Continue searching

Are year-round schools a viable option for improving student achievement, combating summer learning loss in disadvantaged youth, controlling expenses, and reducing teacher burnout?

ProQuest Dissertations and Theses, 2011
Dissertation
Author: Adrienne Smith
Abstract:
Interest in year-round schooling is motivated by international comparisons of time spent in-school and efforts by policymakers to identify viable policy avenues for improving achievement and reducing costs. Prior research on effectiveness of modified year-round schools finds modest support for a modified year-round calendar, but much of the research is weak. Both memory and time-on-task literatures provide a framework for understanding how patterns of schooling and non-schooling intervals could impact student learning. While there is some evidence that the learning losses from summer breaks are greatest for students of low socio-economic status, there are few inquiries into the effects of year round schooling on these students, or other important student subgroups such as English language learners and students in special education. Using an extensive micro-level longitudinal database I compare the achievement of students under a traditional or modified year-round calendars. Capitalizing on a natural experiment in Wake County, NC wherein schools were switched from a traditional to a year-round calendar, I apply a student fixed effects method to isolate the effect of calendar arrangement on student achievement and student absenteeism. To complement the student fixed effects analysis and to increase the study's external validity, I use a growth curve analysis to compare outcomes for students attending a modified year-round calendar to students attending similar schools operating under a traditional calendar. In addition, I examine whether the modified year-round calendar is advantageous for increasing retention and reducing costs. There were five major findings in this dissertation. First, the modified year-round calendar leads to improved student achievement for students of low socio-economic status and second, the modified year-round calendar is also beneficial for students with special needs. Third, the modified year-round calendar is detrimental to student performance for students who are English language learners. Fourth, the link between the modified year-round calendar and lower rates of student absenteeism is supported in the student fixed effects methodology. Fifth, higher teacher retention rates are correlated with a change from a traditional calendar to a modified year-round calendar. Future research efforts are suggested including an investigation of potential mediators for the modified year-round calendar effect.

TABLE OF CONTENTS

LIST OF TABLES

................................ ................................ ................................ ..............................

vi i i

LIST OF FIGURES

................................ ................................ ................................ ................................

x

Chapter

I.

I NTRODUCTION

................................ ................................ ................................ ...........

1

II.

THEORETICAL LITERATURE REVIEW

................................ ................................ ....

7

Memory and Spacing

................................ ................................ ................................ .......

7

Time on Task

................................ ................................ ................................ .................

16

Connection to Calendar

Reform

................................ ................................ ....................

21

III.

POLICY RATIONALE FOR CALENDAR REFORM

................................ ................

25

Summer Learning Loss

................................ ................................ ................................ ..

25

Summer School Interventions

................................ ................................ .......................

29

Modified Year - Round Schools

................................ ................................ ......................

31

Weaknesses in the Current Year - Round Research

................................ ........................

36

In Summary

................................ ................................ ................................ ...................

39

Next Steps

................................ ................................ ................................ ......................

39

IV.

METHODOLOGY

................................ ................................ ................................ ........

4 0

Design

................................ ................................ ................................ ............................

4 0

Research

Questions ................................ ................................ ................................ ........

4 8

Pa rt icipants

................................ ................................ ................................ ....................

49

Measures

................................ ................................ ................................ ........................

49

Dual Methodolo gies

................................ ................................ ................................ ......

5 8

v i i

Data Analysis

................................ ................................ ................................ .................

6 1

Models

................................ ................................ ................................ ...........................

6 4

Limitations

................................ ................................ ................................ .....................

70

V.

RESULTS

................................ ................................ ................................ ......................

7 1

Propensity Score Matching

................................ ................................ ............................

7 2

Descriptive Statistics

................................ ................................ ................................ .....

8 0

Inferential Statistics

................................ ................................ ................................ .......

8 2

Summary and Conclusion

................................ ................................ ..............................

9 1

VI.

DISCUSSION

................................ ................................ ................................ ................

9 3

Summary of Findings

................................ ................................ ................................ ....

9 5

Interpretation and Implications

................................ ................................ ......................

9 6

Limitations

................................ ................................ ................................ ...................

10 2

Suggestions for Future Research

................................ ................................ .................

10 4

Conclusion

................................ ................................ ................................ ...................

10 6

APPENDIC ES

................................ ................................ ................................ ................................ ....

10 7

REFERENCES

................................ ................................ ................................ ................................ ...

1 20

v i i i

LIST OF TABLES

Table

1.

List of Variables

................................ ................................ ................................ ......

5 9

2.

Logistic Regression for Propensity Score Matching: Growth

Curve

A nalysis

................................ ................................ ................................ ...................

7 3

3.

Comparison of Matched and Full Traditional Calendar Samples

to

Modified Year - Round Schools

................................ ................................ ................

7 5

4.

Logistic Regression for Propensity Score Matching: Difference - in -

Differen ces Analysis

................................ ................................ ................................

7 6

5.

Comparison of Matched and Full Traditional Calendar Samples to

Modified Year - Round Schools

................................ ................................ ................

78

6.

Falsification Tests Results

................................ ................................ .......................

8 0

7.

Student Fixed Effects Results for Math and Reading Achievement

.......................

8 2

8.

Growth Curve

Model Results for Math and Reading Achievement

........................

8 4

9.

Student Fixed Effects Results for Student Absenteeism

................................ .........

8 6

10 .

Growth Curve Interactions Results for Student Achievement

................................ .

8 7

11 .

Difference - in - differences Results for Teacher Retention

................................ ........

89

12 .

Difference - in - differences Results for Expenditures

................................ ...............

9 0

B .1 .

Reliability of End of Grade Math Tests (2006). Gender

and

Ethnicity

................................ ................................ ................................ ................

1 0 9

B .2 .

Reliability of End of Grade

Math Tests (2006). Disability

Status,

Limited English Proficiency

................................ ................................ ......

1 0 9

B .3 .

Reliability of End of Grade Reading Tests (2004)

................................ ................

1 0 9

B .4 .

Linkages b etween Research Quest ions

and Specific Analyses

.............................

1 10

B .5 .

Year - Round schools in North Carolina

................................ ................................ .

1 10

B .6 .

Description of Growth Cu rve Sample for Math Achievement

Outcome

................................ ................................ ................................ ................

1 10

B .7 .

Description of Growth Curve Sample for Reading Achievement

Outcome

................................ ................................ ................................ ................

1 1 2

ix

B .8 .

Weighted Description of Student Fixed Effects Sample for Math

Achievement Outcome

................................ ................................ ..........................

1 1 3

B .9 .

Weighted Description of Student Fixed Effects Sample for Reading

Achievement Outcome

................................ ................................ ..........................

1 1 5

B .10 .

Weighted Description of Student Fixed Effects Sample for

Days Absent

Outcome

................................ ................................ ...........................

1 1 6

B .11 .

Description of Difference - in - d ifferences

Sample

................................ ..................

1 1 7

x

LIST OF FIGURES

Figure

1.

Density of Propensity Scores in Traditional Calendar Schools and

Modified Year - rou nd Schools

................................ ................................ ................

7 4

2.

Density of Propensity Scores in Traditional Calendar Wake County

Schools

and Wake County Schools that Switch to the Modified

Year - roun d

................................ ................................ ................................ ..............

7 7

CHAPTER 1

INTRODUCTION

Blue ribbon commissions in the U.S. have acknowledged that the organization and amount of time spent on instruction can influence learning (Berliner, 1990; National Commission on Time and Learning, 1994). Spurred by international comparisons, concern about the traditional US calendar has grown since the mid 1990s (Berliner, 1990; National Education Commission on Time and Learning, 1994).

School districts have experimented with several types of calendar reform including adding days to the school calendar, extending the school day, and modifying the distribution of the 180 days in the standard school calendar ( Beaton et al., 1996 ). Extending the amount of time students spend in school is likely to add additional

costs to compensate teachers for additional hours of work and other costs of school operations. In times when schools are pressured by taxpayer groups and elected officials to operate with limited budgets, calendar reforms such as modifying the school ca lendar emerge as a potential option. Calendar modifications offer three

potential benefits: raising student achievement , improving teacher morale,

and containing costs. Relationships between learning time and student performance are addressed in memo ry a nd time - on - task

research. Both

liter ature strains support the idea that

calendar reform may influence student achievement. Within calendar reform options,

modifying the distribution of the 180 schooling days is an economical choice because instead of req uiring additional time in school, the modified calendar rearranges the 180 schooling days to extend beyond the August to May traditional schooling time span.

Teacher retention is another way to gauge whether calendar reform could gain public support to be come a viable option for reforming schools.

2

The number of modified calendar year - round schools has been steadily increasing since the 1980s. According to the latest figures just over two million children in America are enrolled in modified year - round sch ools ( National Association for Year - Round Education, 2007 ). There were 3,000 modified calendar year - round schools (including schools from kindergarten to twelfth grade) during the 2006 - 2007 school year. Students enrolled in a modified calendar year - round

school

is up 11%

from the 2000 - 20 01 school year and up 39%

from ten years ago. Modified calendars in particular are adopted more readily by elementary schools, as opposed to high schools, because of the scheduling conflicts that arise with after - school a ctivities, especially athletics (St. Gerard, 2007). States with the highest number of modified year - round schools are California, Hawaii, Arizona, Nevada, and Texas; which are also states experiencing high rates of population growth (Cooper, Valentine, Ch arlton, & Melson, 2003).

Modified year - round schooling calendars are commonly arranged by nine weeks of schooling followed by a three week break. The modified year - round calendar eliminates the long summer break. If the time - learning relationship is not only affected by the amou nt of schooling time, but also the length of time between schooling periods, the modified calendar may have an advantage over the traditional calendar. Indeed, research has quantified the summer learning loss phenomenon, which is even more striking for ec onomically disadvantaged students (Alexander, Entwistle, & Olsen, 2001 ; Heyns, 1978 ). Eliminating the long summer break may also be beneficial for other sensitive subgroups unexamined by previous research, such as English Language Learners and students in

special educa tion.

Several literature strands may inform calenda r directives in multiple ways:

1.

An extensive memory literature tradition, with roots in Ebbinghaus‟ s

experiments in the late nineteenth century, uncovers nuances between learning time and m emory ( Dempster, 1989 ). Conceptualizing time in a concrete manner, researchers in this tradition focus on the spacing of learning activities and subsequent memory tests to see if certain patterns of study and varying intervals of time passage increase ret entio n.

3

2.

From Carro ll‟s work springs another line of research focusing

on unpacking time into separate components including student motivation and innate ability, commonly labeled “time on task”

( Carro l l, 1989 ).

Memory studies and the time - on - task literature give insight into the effective use and placement of schooling and non - schooling time periods. I n other words, both

theoretical frameworks speak to calendar reform.

Yet, improving student achievement

is not the only factor in the decision to initiate calendar re form. Calendar reform can

be economical. Interestingly, financial concerns motivated the adoption of a particular kind of modified calendar, referred to as a multi - track year - round calendar, in growing regions. To handle an influx of students and the lack of time and money for building new schools, policymakers have turned their attention toward multi - track modified year - round schools as a feasible cost - savings option. Multi - track schools co ntain several groups of students who follow different schedules. Multi - track schools have a group of students on break at any given time. Each track has its own schedule. For example, a school on a multi - track modified calendar has 4 classrooms designat ed for third graders. There are 5 classes of third graders that rotate through the four classrooms. Every week one class is on a break (referred to as “tracked - out”) while the other four classes are in session. Once a track resumes instruction, they occ upy the classroom where previous students who are now “tracked out” once resided. Thus the school needs fewer classrooms and fewer resources (books, desks, chairs, storage cabinets, etc.) to serve more students. Few studies have quantified the effects

of

multi - track modified calendar schools relative to the traditional calendar (Daneshvary & Clauretie, 2001).

Calendar reform, however easy to manipulate in terms of a policy intervention, experiences the greatest challenge from cultural systems which are s low and oftentimes resistant to change. The standard calendar with 9 months of schooling followed by a three month break was a compromise between urban and rural interests in the early 1900s and is a central structure upon which families and society organ izes their time, including school personnel. The satisfaction of school personnel is a

4

critical component for garnering support for any school reform. Distinct patterns of teacher turnover can reveal a great deal about personnel satisfaction. Higher lev els of teacher turnover can indicate less satisfaction with a reform, in this case, modified school calendars. On the other hand, more frequent breaks in the modified year - round calendar could prevent teacher burnout and lead to a higher rate of teacher r etention. To date, no evidence exists to support or reject the idea that teacher turnover may be lower in modified year - round calendar schools compared to traditional calendar schools.

The main focus of the proposed study is to investigate whether the mod ified year - round calendar improves student achievement outcomes, including the outcomes of groups of disadvantaged students, above and beyond achievement outcomes associated with a traditional calendar. Additional investigations of the school calendar‟s e ffect on school finance and teacher retention will also render evidence as to the potential viability of the modified year - round calendar reform. I hypothesize that, on average, students in modified year - round calendars will outperform students on a tradi tional calendar, and that the differences will be greater for students of low socioeconomic status, English Language Learners, and students in special education. A lso , I predict that schools operating under a modified year - round calendar will spend less p er pupil than schools under a traditional calendar. Finally, I hypothesize that the modified year - round calendar will reduce teacher burnout, resulting in lower teacher turnover rates compared to schools with a traditional calendar.

To study the effect s of modified year - round schools will require three separate approaches . First a comparison of

modified year - round and similar traditional schools over a three year period will yield information on the growth curves

of students from contrasting calendar ar rangements. The lack of methodological and statistical rigor in the literature on modified year - round schooling is only beginning to be addressed by newer studies rooted in Ruben‟s causal framework; capitalizing on

multi - level modeling strategies that ena ble researchers to test between school effects while controlling for individual student and teacher differences. Examining four - year growth curves will give information about the achievement trajectories for modified year - round and traditional students

5

an d speaks to the different trajectories that may be observed in the various subgroups (i.e. students with differing levels of socioeconomic status).

Yet, the growth curve approach

still suffers from bias, namely selection bias. If students who attend a m odified year - round school are systematically different from students who are enrolled in a traditional calendar school in ways that are not measured by control variables such as prior test scores, race/ethnicity, or poverty status then these unobserved dif ferences would confound the calendar effect. For example, perhaps parental motivation

regarding their children‟s success in school

influences the decision to reside in a high growth suburban community

with high performing schools , which increases the chan ce their children will enroll in a year - round school. Differences in student achievement may be due to parental factors ( when they are uncontrolled for in a

study) instead of school calendar arrangement. Conveniently, a natural experiment in North Caroli na allows for a second exploration to estimate

the effect of the modified year - round calendar

with little chance of selection bias .

I n the 2007 - 08 school year ,

Wake County Public Schools switched 23

elementary and middle schools from a traditional calend ar to a modified year - round calendar

just before the school year began, leaving parents with little opportunity to move their children to a school with a traditional calendar . Using a fixed effects design, students serve as their own controls, and statist ical tests contrast

the effect of traditional and modified school

calendars on individual student s . However, to consider the impact estimates unbiased, we have to assume that year - to - year growth is constant over from grade to grade .

Teacher morale, measured by differences in turnover ,

will be addressed using schools i n Wake County with a difference - in - diff erences design. The difference - in - difference s

design will allow a comparison of teacher turnover rates prior to switch to a modified year - round ca lendar, adjusting for the differences due to the passage of time.

Expenditure differences will be examined similarly, where the variables of interest consist of several school - level expenditure categories related to resources (both material and human re sources) that may be affected by calendar reform: regular instruction, special instruction, student services,

6

instructional support, school maintenance and utilities, school leadership, and capital outlay. Note that multi - track modified schools will be th e focus of this analysis. Using difference - in - differences, the effect of calendar arrangement on operational expenditures can be measured. Differences in per pupil spending in various expenditure categories related to calendar type will inform policymake rs as to whether calendar reform is a n efficient or lower cost

alternative.

The proposed study utilizes several advanced research designs and statistical techniques ;

however, limitations remain. First, it i s impossible to know whether all relevant variables have been included in the model. Apart from an experiment that randomly assigns calendar arrangements to schools, sound methodologies that utilize the latest techniques for minimizing bias are needed to estimate the effects of school calendar on student performance. Second, to take of advantage of an exogenous switch in the school calendar, the fixed - effects and difference - in - differences analyses are limited to

a sample of schools from a specific county in North Carolina. The study provides high levels of interval validity but since

Wake County, N orth C arolina

may not be representative of the population of schools that could be converted to a modified year - round ;

the external validity of the effect estimates may be reduced . The remainder of the dissertation

includes a review of the literature on the theoretical framework suggesting benefits for a modified school calendar ( Chapter 2 ), the policy rationale behind c alendar reform ( Chapter 3 ) ,

details the methodology behind the current study ( Chapter 4 ) , presents model results ( Chapter 5 ), and discusses findings with suggestions for future research ( Chapter 6 ) .

CHAPTER 2

THEORETICAL LITERATURE REVIEW

Calendar reform restructures schooling and non - schooling time. Depending on the reform, calen dar changes may increase the effectiveness of schooling time because of

qualitative differences in schooling that occur base d

on the s pecific spacing of learning sessions .

Both memory and time - on - task theories provide a context for understanding how patterns of schooling and non - schooling intervals impact student learning. Next is a description of the literature in mass versus distributed theory and theories based on the time - on - task conceptual framework.

Memory and Spacing

The central difference between the modified year - round calendar and the traditional calendar is the distribution of in - school and out - of - school time. The traditional calendar lumps together in - sch ool time while the modified year - round calendar creates chunks of in - school time (on average ,

nine

weeks) separated

by out - of - school time (on average ,

three

weeks). The effect of the dispersion of in - school learning time in each calendar arrangement may b e examined through the mass versus distributive practice theoretical frame. The traditional calendar can be compared to the mass condition, where learning time is massed together in one period, while the modified year - round calendar is likened to the spac ed condition, where learning time is divided into multiple periods. Next, is a literature review of the spacing effect including a summary of various theories attempting to account for the phenomena and landmark studies within the field.

Early Learning Th eory

The spacing effect is grounded in early learning theory . Performing memory experiments on himself

in the late nineteenth century , Ebbinghaus surmised that spacing learning trials improved

8

retention compared to learning trials packed

closely together (aka “the spacing effect”). Ebbinghaus‟ s

groundwork

spurred a number of studies on the spacing effect in the early twentieth century ( Dempster, 1989 ). Although methodological procedures were far less advanced, many of the studies confir med the presence of the spacing effect.

Within the context of early learning theory, the two main facets of learning are :

changes in resistance t o forgetting and changes in lag time between

a

question and an answer (Estes, 1955). According to Estes, bot h facets, combating forgetting and reflex response ,

are in line with Skinner‟s work on the use of reinforcement schedules that increase or decrease the likelihood of eliciting a specific behavior ( Skinner, 1938 ). Labeled “habit strength” and “response str ength , ” Estes quantifies both facets through a series of probability curves. Using this approach he finds that the number and spacing of conditioning episodes is related to habit strength , meaning that forgetting can be manipulated by changing the number of learning occasions and the amount of time between learning occasions . Increasing the time interva l between conditioning episodes results

in greater retention. Response strength

(how quickly a participant answers a question)

appears greater with very s hort intervals between conditioning episodes at first, but over time spaced conditioning episodes tend to produce faster recall (Estes, 1955). Grounded in behaviorism, Estes reasons that improved retention is a direct function of the number of similar ele ments between conditioning episodes and recall trials . This approach is later fleshed out by component level theorists

(Glenberg, 1979).

Defining the Spacing Effect

A flurry of research occurred in the 1960s and 1970s, when different theories such as the components level theory, were put forth to help further explain the consistency of the spacing effect. Interest in the relationship between studying intervals and retention resulted in an explosion of experiments. For example, students studied spelling t hrough six computer exercises that were either spaced one day apart (the spaced condition) or all occurred on the same day (the massed condition) (Fishman, Keller, & Atkinson, 1968).

Memory tests of this sort revealed differences in retention for

9

particip ants in spaced versus massed conditions, favoring spaced conditions with remarkable regularity ( Hintzman, 1974; Melton, 1970 ).

Dempster‟s (1989)

review

of spacing effect research

summarizes several important features of the spacing effect that have been

highlighted repeatedly in the literature. First, the overall size of the spacing effect is pronounced, especially compared to other learning variables which have comparably weaker effects. Second, the size of the retention interval

(the amount of time b etween the last learning episode and the test)

is also related to the size of the spacing effect with longer retention intervals favoring more spaced learning trials. Contemporary research has focused on this aspect

of the

spacing effect

and is detailed l ater in the review . Third, it

appear s

that the spacing effect has some boundaries, specifically

in terms of material

and

context. Massed reading passage trials were just as effective as spaced reading passage trials ( Austin, 1921 ). Recalling nonsense sy llables may be less influenced by the spacing effect phenomenon

than the acquisition of more meaningful information

(Underwood, 1961). However, even though some material may be less amenable to the spacing effect, the spacing effect has been evidenced in virtually all traditional learning tasks (see Dempster, 1989

for full review).

There may also be a developmental component to the spacing effect. Toppin and DiGeorge (1984)

postulated that the neural mechanisms associated with the spacing effect mature

in time. Using evidence from

similar experiment s

performed with presc hoolers and first graders,

the spacing effect was present for first graders, but not for preschoolers. However, other researchers have reported effects in young children ( Cornell, 1980 ;

Rea &

Modigliani, 1987 ). By and large, the spacing effect is extremely robust over different subject matter, interval spacing, and throughout a long research history.

Encoding Variability Theory

Explanations for t he spacing effect can be classified into two categories; encoding variability theories and deficient - processing theories

(Hintzman, 1974) . Underlying the encoding variability theory is the assumption that information is encoded and that as the number of encodings increases so

10

does the number of pathways for retrieval. The explanation for recall differences between participants in massed versus distributed conditions is due to partial versus full processing. In massed conditions, repeated trials spaced closely together require less processing be cause simple retrieval of the previous encoding is so accessible. The spaced condition requires deeper processing upon each trial because the prior encoding happened longer ago. Using deeper processing for successive trials is what encoding variability r esearchers believe accounts for the higher long - term retention of participants in a spaced versus massed learning condition. Addressing the need for further explanation of the role of context within the encoding variability theory, Glenberg (1979) provide s a more explicit account in his component level s

theory.

Component Levels Theory

In an effort to explain the spacing effect, Glenberg (1979)

describes the component - levels theory which outlines three types of components in relation to the retrieval proc ess. In component - levels theory various stimuli are encoded by the individual either voluntarily or involuntarily resulting in the formation of a complex episodic trace. Multiple components make up the episodic trace; contextual components, structural co mponents, and descriptive components. Contextual components include all stimuli related to the individual‟s environment, including the physical setting, time of day, and the individual‟s mental and emotional state. Contextual components are encoded autom atically. When information is encoded in different contexts, the amount of contextual components increases. With more contextual components to aid in retrieval of the episodic trace, an individual is more likely to recall information. Unlike contextual components, structural components are encoded based on an individual‟s voluntary processes to manage new information. The ways in which an individual organizes

or chunks information together is the structural components part of the episodic trace. Lastly , descriptive components relate new information with prior experiences. By linking the semantic memory to the input of new information, the descriptive components are formed on a deeper level of processing. Glenberg (1979) reasons that spaced learning co nditions allow for greater exposure to a rich set of contextual components and more opportunities to utilize different structural

11

and descriptive components to create a

more elaborate memory trace

resulting in higher

rates of retention .

Component - level s

theory goes

one step further by attributing the encoding feasibility to different features of the trial process that create an “episodic t race .”

Full document contains 141 pages
Abstract: Interest in year-round schooling is motivated by international comparisons of time spent in-school and efforts by policymakers to identify viable policy avenues for improving achievement and reducing costs. Prior research on effectiveness of modified year-round schools finds modest support for a modified year-round calendar, but much of the research is weak. Both memory and time-on-task literatures provide a framework for understanding how patterns of schooling and non-schooling intervals could impact student learning. While there is some evidence that the learning losses from summer breaks are greatest for students of low socio-economic status, there are few inquiries into the effects of year round schooling on these students, or other important student subgroups such as English language learners and students in special education. Using an extensive micro-level longitudinal database I compare the achievement of students under a traditional or modified year-round calendars. Capitalizing on a natural experiment in Wake County, NC wherein schools were switched from a traditional to a year-round calendar, I apply a student fixed effects method to isolate the effect of calendar arrangement on student achievement and student absenteeism. To complement the student fixed effects analysis and to increase the study's external validity, I use a growth curve analysis to compare outcomes for students attending a modified year-round calendar to students attending similar schools operating under a traditional calendar. In addition, I examine whether the modified year-round calendar is advantageous for increasing retention and reducing costs. There were five major findings in this dissertation. First, the modified year-round calendar leads to improved student achievement for students of low socio-economic status and second, the modified year-round calendar is also beneficial for students with special needs. Third, the modified year-round calendar is detrimental to student performance for students who are English language learners. Fourth, the link between the modified year-round calendar and lower rates of student absenteeism is supported in the student fixed effects methodology. Fifth, higher teacher retention rates are correlated with a change from a traditional calendar to a modified year-round calendar. Future research efforts are suggested including an investigation of potential mediators for the modified year-round calendar effect.