Jumping exercises/correct leads?

Okay, so I am training my project horse out of just doing trails, into being pretty much an eventing horse, but I have 2 questions/problems. Since he was a trail horse, he was never told what was wrong and what was right with his gaits, neck, etc., so he ALWAYS takes his right lead, but it is nearly impossible for him to get his left lead unless we get it over a ground pole or jump. Suggestions? Also, I need some good jumping exercises. We only jump up to 2' for now, but we get bored like that, and I don't want to move up until we are both ready, which we aren't. Any suggestions on good jumping exercises I could do? I have 6 jumps and 9 poles if that helps any.

I certainly am not an expert at this but, you could maybe set up like 2 ground poles and than a x-rail, do some gymnastics, or bounces.

I know what you mean about your trail horse only picking up the right lead. I started last year with showing my mare and she still wouldn't pick up the left lead. Something you can do is to lunge them in a small circle to the left. Once they pick up the correct lead for one stride stop praise them and try for two. I did my first day like that and she got on the left lead for a 1/4 circle then switched so I stopped. The next day did it again. I am now able to do a 3/4 of a circle. Part of it is the fact that she hasn't built her muscles up on that side like she has on the other side.

As far as jumping I know nothing.