One of the things we did in football was called a box squat to improve our vertical. I was a FS, so my vert was of the utmost importance. Basically, you would place a box, or a bench if you are in the gym under your rear when you squat. You squat until you hit the bench with your ass then drive the weight back up with an explosive force. That plus leg press, plyometrics and even sprints should help your vert. The tricky thing in a gym is to adjust a bench to the appropriate height. We had custom manufactured boxes just for this movement. You'll probably have to throw a plate or two under the bench dependent on your height.
And yes, continue doing regular squats as well. I would avoid high reps and stick to 4 sets at 6-10 reps. You want to focus on strength as much as possible.The more strength your legs have, the higher you will leap. Do your box squats a couple days later and work the plyo and sprints in between. In college off-season, we hit the weights hard M,W,F and did our conditioning T,TH,Sat.