Evidence for Learning: Extending school time

Extending school time

Moderate impact for moderate cost based on limited evidence
Implementation cost
Evidence strength
Impact (months)

Extending school time involves increasing learning time in schools during the school day or by changing the school calendar. This can include extending core teaching and learning time in schools as well as the use of targeted before and after school programs (including additional small group or one to one tuition). It also includes revisions to the school calendar to extend the total number of days in the school year.

Other approaches to increasing learning time are included in other sections of the Toolkit, such as homework, and summer schools.

1. Programs that extend school time have a positive impact on average but are expensive and may not be cost-effective for schools to implement. Schools will also need to consider the workload and wellbeing of their staff.

2. Planning to get the most from any extra time is important. It should meet students’ needs and build on their capabilities. Where additional time is voluntary, it is important to monitor attendance to ensure students who need additional support can benefit.

3. Before and after school programs with a clear structure, a strong link to the curriculum, and well-qualified and well-trained staff are more clearly linked to academic benefits than other types of extended hours provision.

4. Additional school time may be more effective if it is used for one to one support, in contrast to small or large group teaching.

5. Enrichment activities without a specific focus on learning can have an impact on achievement, but the effects tend to be lower and the impact of different interventions can vary a great deal (see entries for physical activity or arts participation). These interventions may, however, be beneficial for their own sake outside of any achievement impacts.

The average impact of approaches involving extending school time is about an additional three months’ progress over the course of a year. The average impact is influenced by the targeted use of before and after school programs, which have higher impacts on average. The impact is also slightly lower when school time is extended in secondary school.

In addition to providing academic support, some school programs aim to provide stimulating environments and activities or develop additional personal and social skills. These programs are more likely to have an impact on achievement than those that are solely academic in focus. However, it is not clear whether this is due to the additional activities or to improved attendance and greater engagement.

The research also indicates that attracting and retaining students in before and after school programs is harder at secondary level than at primary level. To be successful, any extension of school time should be supported by both parents and staff. It should also be noted that more extreme increases may have diminishing effects if engagement of students is reduced. 

While the impact on academic achievement is, on average, positive, the cost of extending school times might mean that it is not a cost-effective approach to implement at the school level without additional funding.

  • More studies have been undertaken in primary schools. Effects are higher, on average, for primary (+3 months) than secondary schools (+2 months).

  • Most of the evidence relates to literacy and mathematics with similar effects in both subjects.

  • More intensive approaches in extended time, such as one to one, appear to be more effective than either small group or large group teaching.

  • Most studies have been conducted in the USA – this could pose a risk to the transferability of findings, as impacts may be influenced by the average length of education in any given context. 

There is some evidence to suggest that disadvantaged students might benefit more from additional school time.

To increase the likelihood of additional school time benefitting disadvantaged students, school leaders should consider how to secure engagement and attendance among those from disadvantaged backgrounds. It is possible that if targeted tuition or enrichment activities are offered universally, those who could benefit the most would be the least likely participate or engage. Adopting a more targeted approach also has its challenges though, as selected students may feel singled out and stigmatised.

Additional non-academic activities may also provide free or low-cost alternatives to sport, music, and other enrichment activities that more advantaged families are more likely to be able to pay for outside of school.

The theory of change for extending school time is that extra hours of allocated learning time mean that students have more exposure to teaching, more time to engage with content and generally a greater amount of learning. When implementing approaches that extend school time it is important to acknowledge that allocated learning time and actual learning time are not the same thing. Schools should:

  • Carefully monitor attendance to ensure that extensions to the school day or term do not lead to reductions in overall learning time for some students.
  • Carefully consider and monitor student engagement – if more time is spent managing student behaviour in a longer school day then engaged learning time may not increase.
  • Monitor staff wellbeing and workload to ensure that additional teaching time does not reduce quality (e.g. through less time for professional development or planning lessons).

Extending school time is likely to require a significant reconfiguration of working patterns for staff, especially if this involves an altered school calendar. It is important school leaders are clear on the purpose of introducing additional learning time and secure parental support prior to making changes.

Approaches to extending school time are likely to be spread over an academic year. Some schools may also decide to target additional support at specific classes or students during particular school terms or times of the year.

When introducing new approaches, schools should consider implementation. For more information see Putting Evidence to Work – A School’s Guide to Implementation.

Overall, costs are estimated as moderate. The average cost of teaching a student is about $2,500 a year ($13 per day) in primary school and about $3,500 a year ($18 per day) in secondary. Extending the school year by two weeks would therefore require about $260 per student per year for primary schools and about $360 per student per year for secondary. Estimates suggest after school clubs cost, on average, $7 per session per student. A weekly session would therefore cost $273 per student over the course of a 39-week school year.

If additional teachers are not hired to cover the increases in teaching time that comes from extending school time, any increases to school calendars or timetables may also require a large amount of staff time, compared with other approaches.Alongside time and cost, school leaders should consider how to ensure the quality of teaching during additional school time and avoid approaches that could increase teacher workload without making significant impacts on student learning.

The security of the evidence around extending school time is rated as moderate. 74 studies were identified that meet the inclusion criteria of the Toolkit. Overall, the topic lost an additional padlock because a large percentage of the studies are not randomised controlled trials. While other study designs still give important information about effectiveness of approaches, there is a risk that results are influenced by unknown factors that are not part of the intervention.

As with any evidence review, the Toolkit summarises the average impact of approaches when researched in academic studies. It is important to consider your context and apply your professional judgement when implementing an approach in your setting.

Evidence strength
Number of studies74
Review last updatedJuly 2021