Need some inspiration till I get my 101 schooling exercises book. Can only do walk (horse recovering from tendon injury) but can do lateral stuff ie leg yield/turns on forehand
I would try doing a PSG dressage test in walk - they are fairly complex - and will prove a test just trying to remember it!.
or draw a 'map' of your drive to work/shops/grannies ect, and go around all the roundabouts and corners in your mind around the school!