AI tool reduced primary teachers’ lesson planning time by a quarter, but views on the tool were mixed

Teachers using Aila spent an average of two and a half hours a week planning lessons and preparing resources, compared with three hours and 19 minutes for the group who were not using the tool. This equates to an average saving of around 49 minutes a week.

Teachers earlier in their career or with less confidence in their subject knowledge were more likely to find Aila useful and reduce lesson planning workload.

However, teachers’ use of and views about the tool were mixed. While some found Aila accessible, aligned with the curriculum and useful when planning lessons on unfamiliar topics, others preferred to adapt existing lessons plans or use other tools.

This may reflect Aila’s main function of preparing new lessons from scratch, where more experienced teachers preferred to modify existing lesson plans.

Both the frequency and amount of use of the tool declined over the ten-week trial.

The findings come from a randomised controlled trial involving 464 teachers in 108 schools. The evaluation was commissioned and published today by the EEF and carried out by National Foundation for Educational Research (NFER).

The findings echo those of a previous EEF trial evaluated by NFER and published in December 2024, which examined teachers’ use of ChatGPT to support lesson planning. That trial found that teachers using ChatGPT spent 69% of the total time spent by a comparison group asked to plan lessons without using any AI tools. This trial also found that use of ChatGPT declined during the 10-week trial period.

The findings of both trials received a ​‘high’ security rating from the EEF, which means there is a high degree of confidence in the results.

The publication of today’s results continues the EEF’s commitment to develop the evidence base on the use of AI in education. This includes a £2.5m research fund to explore how generative AI affects learning, including the phenomenon of cognitive off-loading.

More details of the trial and results

This ​‘Teacher Choices’ trial tested the use of Aila, an AI-powered lesson assistant designed to support teachers with lesson planning and resource creation from scratch.

To use the tool, teachers select a year group, subject, and topic. Aila suggests a learning objective, based on the National Curriculum, and activities to use in the lesson. Teachers then work to refine the plan, either with Aila or offline.

The trial involved primary school teachers teaching Key Stage 2 (ages seven to 11) in the Autumn 2025 term. Aila usage was measured through weekly teacher diaries, supported by interviews and school visits.

One group of teachers were encouraged to use Aila to plan lessons, while a comparison group of teachers were told to not use Aila. However, the comparison group were free to use other AI tools.

The evaluation found that:

• Teachers who used Aila spent 76% of the time on resource and lesson preparation compared with teachers not using the tool.
• New teachers and teachers with less confidence in their subject knowledge were more likely to experience reduced lesson planning workload.
• In practice, many teachers used Aila alongside their existing planning processes, with some preferring these or other tools to Aila.
• 81% of teachers in the Aila group used the tool at least once.
• Use of Aila declined over the duration of the trial.
• In a post-trial survey, fewer than one in five teachers felt that using the tool meaningfully influenced their teaching and planning. This could reflect a range of factors, such as high levels of confidence in lesson planning at the start of the trial though.