Grid, bounce and canter poles exercise
Warm up over two bounces (pole, fence, pole) on the corners a couple of times on each rein so that the horse understands what you require before you put the exercise together, coming down the grid first.
This exercise incorporates a line of four fences, with one stride in between and set at different heights so that the horse has to adjust itself.
After coming down the line, make a good turn into the pole, fence, pole bounce which really makes the horse work hard and use its hind leg. You need to collect quickly after coming down the grid in order to jump the bounce.
Then you need to ride straight to canter over the four canter poles, before coming back down the grid and then riding on the other rein.