We found it really helpful to go over our Cheat Sheet just before our exams too

Waiting outside an exam room is a horrible business.
We dont recommend ever studying new information in this time its way too late. What will be will be.
But looking over a Cheat Sheet will give your teen something to do, and let them consolidate all those nasty little facts they need to remember.
If they want to be really sneaky as soon as they get into the exam room they can jot down the ones they always struggle to remember on the inside cover of their paper. When the time comes during the exam they need that bit of information, itll be right there staring them in the face.
Using colour in a Cheat Sheet helps some students particularly visual learners, as they come to associate a certain fact with a specific colour. Its worth giving this a go anyway irrespective of what your teens predominant learning style is.