Inclusion Criteria
To be included in this review, a study had to do the following
- be published in a journal or government report
- evaluate the effect of increased in-school learning time alone (independent of other intervention components)
- evaluate interventions implemented in K-12 schools
- not evaluate full vs. half-day kindergarten (topic previously reviewed)
- not assess an exclusively special needs population
- have a concurrent comparison group or before-after comparison; cross-sectional studies and post-intervention only studies were excluded
- include comparison groups that were either exposed to routine school time or to lesser amounts of expanded time than the intervention group
- report >1 outcome of interest: academic achievement, cognition, social or emotional skills, delinquent behaviors
- be published in English; and
- be conducted in a high-income nation (World Bank List
)
The number of studies and publications do not always correspond (e.g., a publication may include several studies or one study may be explained in several publications)..
Effectiveness Review
Angrist JD, Pathak PA, Walters CR. Explaining charter school effectiveness. Am Econ J: Appl Econ 2013:5(4):1–27.
Bellei C. Does lengthening the school day increase students’ academic achievement? Results from a natural experiment in Chile. Econ Educ Rev 2009: 29: 629–40.
Bishop J, Worner W, Weber L. Evaluation Studies, extending the school day: an evaluation study of a seven-period class schedule. Studies in Educational Eval 1988:14:361–80.
Checkoway A, Gamse B, Velez M, Caven M, de la Cruz R et al. Evaluation of the Massachusetts Expanded Learning Time (ELT) Initiative, year five final report, 2010-2011, Volume I. Cambridge: Abt Associates, 2012.
Dobbie W, Fryer RG. Getting beneath the veil of effective schools: evidence from New York City. Am Econ J: Appl Econ 2013:5(4):28–60.
Eren, O and Millimet DL. Time to learn? The organizational structure of schools and student achievement. Empirical Econ 2007:32:301–32.
Frazier JA, Morrison FJ. The influence of extended-year schooling on growth of achievement and perceived competence in early elementary school. Child Devel 1998:69(2):495–517.
Hoxby CM, Murarka S, Kang J. How New York City's charter schools affect achievement, August 2009 report. Second report in series. Cambridge, MA: New York City Charter Schools Evaluation Project, September 2009.
Gleason P, Clark M, Clark Tuttle C, Dwoyer E. The evaluation of charter school impacts, final report (NCEE 2010-4029). Washington (DC): National Center for Education Evaluation and Regional Assistance, Institute of Education Sciences, U.S. Department of Education, 2010.
Kraft MA. How to make additional time matter: integrating individualized tutorials into an extended day. Educ Finance and Pol 2015:81–116. doi:10.1162/EDFP_a_00152.
Lavy V. Expanding school resources and increasing time on task: effects on student’s academic and non-cognitive outcomes. Cambridge (MA): National Bureau of Economic Research. Working paper 18369, 2012.
Assessing and Summarizing the Evidence on Effectiveness
Study Abstraction and Quality Assessment
Two reviewers independently evaluated each study meeting our inclusion criteria, including studies from the two existing systematic reviews and those found in the update search. Information on study methods, results, and interpretation was abstracted using standard Community Guide criteria
[PDF - 6.80 MB]. Disagreements between reviewers were resolved by consensus. Using Community Guide methods
[PDF - 240 kB], each study was assessed for study design and threats to internal and external validity, including inadequate descriptions of the intervention, population, and sampling frame; inadequate measurement of exposure or outcome; inappropriate analytic methods; high attrition; or failure to control for confounding. Study quality of execution was characterized as good (0–1 threats to validity), fair (2–4 threats), or limited (>4 threats). Studies of limited quality of execution were excluded from analysis.
Primary and Secondary Outcomes of Interest
Education achievement is counted as an indicator of long term health benefit in this review since it is an established determinant of long term health outcomes. Intervention impact on educational achievement was assessed by changes in standardized test scores or grade point average. Changes in other outcomes were qualitatively assessed.
Statistical Analysis and Synthesis of Results
We present results separately for studies that examined lengthened school day, those that examined lengthened school year, and those that examined both changes combined; no studies examined lengthened school week. Depending on data provided in each study, effect estimates were calculated using relative percent change, absolute percentage point change, or standardized mean difference (SMD). When metrics allowed, effect estimates from individual studies were pooled to calculate a median. When at least five individual effect estimates were available, interquartile intervals (IQIs) were calculated to provide a measure of variation; otherwise, the range of estimates was indicated. Studies without metrics or data to allow direct comparison with other studies were narratively summarized. Some studies reported multiple effect estimates per outcome (e.g., language, math, or science scores); mean effects were calculated to prevent counting studies more than once. When relevant data were available, we transformed increased time reported into hours per year. Analyses were performed in 2016–2017.
The CPSTF findings are based on evidence from a systematic review with 11 included studies (search period through February 2015). Studies that met inclusion criteria published prior to 2010 were identified from two high quality existing systematic reviews identified through the search (Patall et al., 2010; Redd et al., 2012). Included studies published after 2010 were identified using the search strategy listed below.
Effectiveness Review
The following databases were searched for English-language papers that evaluated the impact of modified school time programs:
- CAB Abstracts
- CINAHL
- EconLit
- ERIC
- Federal Research in Progress
- Global Health
- Medline
- NEA
- PsycINFO
- PsycCritiques
- Scopus
- Sociological Abstracts
The literature search covered interventions modifying school time by either expanding school time or rearranging school calendar without expanding school time. For the review on expanded in-school learning time, Community Guide staff screened search results twice to identify papers specific to this intervention.
Following are the search strategies used for this review.
Databases: [all on EBSCOHost] CINAHL, EconLit, Federal Research in Progress
Date Searched: 2/20/2015
S8 TI 12 month school* OR twelve month school*
S7 TI year round schooling
S6 TI year round education
S5 TI year round education
S4 TI all year school
S3 TI all year school AND TI ( "school day" or "school days" or "school hours" or "instructional hours" or "instructional time" or "class time" or "classroom time" or "classroom hours" )
S2 TI increase* AND TI ("school day" or "school days" or "school hours" or "instructional hours" or "instructional time" or "class time" or "classroom time" or "classroom hours")
S1 TI "saturday school" OR TI "longer school week"
TI (longer or lengthen* or extended or extending or extend or expand* ) AND TI ( school day* or school week or school time or school hours or school year or instructional hours or school calendar or learning time )
Databases: [all on OVID] Medline, Global Health, PsycINFO, PsycCritiques, CAB Abstracts
Date Searched: 2/20, 23/2015
- ((longer or lengthen* or extended or extending or extend or expand*) and (school day* or school week or school time or school hours or school year or instructional hours or school calendar or learning time)).ti.
- ((longer or lengthen* or extended or extending or extend or expand*) and (school day* or school week or school time or school hours or school year or instructional hours or school calendar or learning time)).su,kw.
- ((longer or lengthen* or extended or extending or extend or expand*) and (school day* or school week or school time or school hours or school year or instructional hours or school calendar or learning time)).sh,kf,kw.
- year round school.ti,kf,kw,sh.
- (year round school or 12 month school or twelve month school).ti,sh,kw.
- 5 not 4
- (saturday school or saturday classes).ti,sh,kw.
- ((longer or lengthen* or extended or extending or extend or expand*) and (school day* or school week or school time or school hours or school year or instructional hours or school calendar or learning time)).ab.
- ((longer or lengthen* or extended or extending or extend or expand*) and (classroom time or classroom hours or instructional time or learning hours)).ti,sh,kw.
- (classroom hours and academic achievement).mp.
- ((school day or school time or classroom time or classroom hours) and academic achievement).mp.
- from 1 keep 1-29
- from 4 keep 1-7
- from 7 keep 1-5
- from 9 keep 1
- from 11 keep 18, 110, 121, 123, 148, 151...
- (length* adj2 school day*).ab.
- saturday school.ab.
- longer school week*.ab.
- ((extend* adj2 school day*) or (extend* adj2 school week) or (extend* adj2 instruction* hours)).ab.
- ((expand* adj2 school day*) or (expand* adj2 school week) or (expand* adj2 instruction* hours) or (extend* adj2 school calendar*) or (expand* adj2 school calendar*) or year round school).ab. ear round education.ab.
- ((increase* adj2 school day*) or (increas* adj2 school week) or (increas* adj2 instruction* hours) or (increas* adj2 school calendar*) or (increas* adj2 school year) or (increas* adj2 school week)).ab.
- ((increase* adj2 school day*) or (increas* adj2 school week) or (increas* adj2 instruction* hours) or (increas* adj2 school calendar*) or (increas* adj2 school year) or (increas* adj2 school week)).ab.
- ((increase* adj2 school day*) or (increas* adj2 school week) or (increas* adj2 instruction* hours) or (increas* adj2 school calendar*) or (increas* adj2 school year) or (increas* adj2 school week)).ab.
- (increas* adj2 instruction* hours).ab.
- (longer adj2 (instruction* hours or school day* or school week or school hours or school year* or school term* or learning time* or school calendar)).ab.
- year round schooling.ti,ab,kw.
- (length* adj2 (school hour* or school day* or school year or school calendar or school schedul* or school term*)).ti,ab,kw.
- or/1-13
Databases: [all on Proquest] ERIC, Social Services Abstracts (1979 - current), Sociological Abstracts? (1952 - current), ProQuest Family Health, ProQuest Health & Medical Complete, ProQuest Psychology Journals, ProQuest Research Library, ProQuest Social Science Journals, ProQuest Sociology (1985 – current)
Date Searched: 2/20/2015
S36 ti("year round education")
S35 ti("expanded instructional time")
S34 ti("expanded instructional hours")
S33 ti("twelve month school")
S32 ti("12 month school")
S31 ti("12 month school")
S30 ti("year round school")
S29 ti("longer school calendar")
S28 ti("longer school calendars")
S27 ti("extended school calendars")
S26 ti("extended school calendar")
S25 ti("extended school year")Limits applied
S24 ti("extended school year")Limits applied
S23 ti("extended school year")
S22 ti("extended instructional")
S21 ti("extended school time")
S20 ti("extended school days")
S19 ti("extended school day") or ti("extendeded school days")
S18 ti("longer school day") or ti("lengthened school days")
S17 ti("longer the school day") or ti("longer school days")
S16 ti("expanded school day")
S15 ti("lengthening the school day")
S14 ("lengthening the school day")Limits applied
S13 ("lengthening the school day")
S12 ("longer school day")Limits applied
S11 ("longer school day")
S10 ("lengthen school day")
S9 ti("increase* school day")
S8 ti(extended OR extending OR expand OR expanded OR expanding OR increase OR increased OR increasing OR lengthen OR lengthened OR lengthening or longer or Saturday*) AND ti((school* OR instructional or learning))Limits applied
S7 ti(extended OR extending OR expand OR expanded OR expanding OR increase OR increased OR increasing OR lengthen OR lengthened OR lengthening or longer or Saturday*) AND ti((school* OR instructional or learning))
S6 "year round school" OR ("school all year round" OR "12 month school year") OR ("twelve month school year" OR "year round education")
S5 ti(extended OR extending OR expand OR expanded OR expanding OR increase OR increased OR increasing OR lengthen OR lengthened OR lengthening or longer or Saturday*) AND ti((school* OR instructional or learning or day or days))
S4 ti(extended OR extending OR expand OR expanded OR expanding OR increase OR increased OR increasing OR lengthen OR lengthened OR lengthening or longer or Saturday*) AND ti((school* OR instructional or learning or day or days))
S3 ti(extended OR extending OR expand OR expanded OR expanding OR increase OR increased OR increasing OR lengthen OR lengthened OR lengthening) AND ti((school* OR instructional or learning or day or days))
S2 ti(extended OR extending OR expand OR expanded OR expanding OR increase OR increased OR increasing OR lengthen OR lengthened OR lengtheneding) AND ti((school* OR instructional or learning or day or days))
S1 (extended or extending or expand or expanded or expanding or increase or increased or increasing or lengthen or lengthened or lengtheneding) AND (school* OR instructional or learning or day or days)
ti("extended school week") or ti("Saturday school")Limits applied
S4 ti("extended school week") or ti("Saturday school")
S3 ti("longer school week")
S2 ti("year round schooling")
S1 ti("year round schooling”
ti("longer school week")
S3 su(saturday school programs)or su(“Saturday school programs”)
S2 su(saturday school effectiveness)
S1 su(extended school year)Limits applied
Database: Scopus
Date Searched: 2/20/2015
( TITLE-ABS-KEY ( "extended school day" ) ) OR ( TITLE-ABS-KEY ( "extended school hours" ) ) OR ( TITLE-ABS-KEY ( "length of school day" ) ) OR ( TITLE-ABS-KEY ( "year round school" OR "12 month school" OR "twelve month school" ) ) OR ( TITLE-ABS-KEY ( "saturday classes" OR "saturday school" OR "longer school week" OR "lengthened school week" OR "expanded school week" OR "increased school hours" OR "increased school week" ) ) OR ( TITLE-ABS-KEY ( "extending the school day" OR "extending the school year" OR "lengthening the school day" OR "lengthening the school year" ) )
Angrist JD, Pathak PA, and Walters CR. Explaining charter school effectiveness. American Economic Journal: Applied Economics 2013:5(4):1-27.
Dobbie W and Fryer RG. Getting beneath the veil of effective schools: evidence from New York City. American Economic Journal: Applied Economics 2013:5(4):28–60.
Hahn RA, Truman BI. Education improves public health and promotes health equity. International Journal of Health Services 2015;45(4):657-78.
Hoxby CM, Murarka S, and Kang J. How New York City's Charter Schools Affect Achievement, August 2009 Report (second report in series). Cambridge (MA): New York City Charter Schools Evaluation Project, September 2009.
Knopf JA, Hahn RA, Proia KK, Truman BI, Johnson RL, et al. Out-of-school-time academic programs to improve school achievement: a Community Guide health equity review. Journal of Public Health Management & Practice 2015;21(6):594–608.
Patall EA, Cooper H, and Allen AB. Extending the school day or school year: a systematic review of research (1985-2009). Review of Educational Research 2010;80(3):401-36.
Redd Z, Boccanfuso C, Walker K, Princiotta D, Knewstub D, and Moore K. Expanding Time for Learning Both Inside and Outside the Classroom: A Review of the Evidence Base. New York (NY): The Wallace Foundation, August 2012.