Cook with lids on. Regularly putting lids on pans is quicker, wastes less heat and is cheaper.

Here is an educational opportunity based on this idea (for 7-10 year olds) and it helps understand saving energy.

This is extended in a two part experiment for slightly older scientists: part 1 is suitable for 11-13 year olds and older and part 2 for more advanced learners (14-16 year olds).

These can be copied and amended as required by teachers and parents.