Teachers say new Leaving Cert reforms could be too ambitious and hard to deliver.
Submissions to the curriculum council reveal widespread concern over workload, safety, and student stress.
Newly released documents show teachers and scientists warned that plans to give students 40 per cent of their Leaving Cert marks for project work may be unmanageable.
They raised safety concerns about handling experiments, as well as fears the workload could put students off taking multiple science subjects.
The National Council for Curriculum and Assessment says it revised the courses after reviewing the feedback and will carry out early reviews to ensure the new system works for schools, according to the Sunday Independent.
The first of the new continuous assessments is underway this school year, as part of a wider overhaul of the Leaving Cert due to be completed by 2029.