Ball rollout: make sure your plank position is maintained! This is very good for core strength and balance
Single leg ball rollout: wowza, this one is tough and you will definitely know which is your weak leg after this!
Extended arm sit up: you already know how to do a crunch now just add a plate and go to work! But make sure your abs are still doing the work, don’t let your arms and the pushing motion drive the exercise
Ball pass
Ball pass crunch: add the crunch to get a bonus ab w