You don't have to pay after your intro session, you have free time afterwards to do what you please (part of intro session). I think there was about 30 min of free time left when I did mine 3-4 years ago.
It seems like you want to learn the tricks you mentioned into a foam pit. Just to let you know, Woodward at Copper no longer has snowflex, they have these roller-skis (I don't know what you call them) on a wood drop-in.
If you want to learn on a trampoline that'd be much easier and more likely with 30ish minutes. There's an unbelievably nice trampoline named "the Supertramp" that is spectacular. 3 of my friends learned their first dubs on it in the span of about 20 minutes. There is also the option to travel off another trampoline into a foam pit.
The coaches are pretty good, they know their stuff, but the most they typically do is tell you what you're doing wrong. They have solid advice, but they don't really work through the progression of the trick with you which is understandable because their main job is to watch everyone and keeps things safe.
If I were you, I'd try to persuade your parents to buy you a drop-in session or find a way to pay for one, because it's definitely worth it after doing the intro. You'll have a great time whatever you do, I was lucky enough to have Ian Compton in my intro class/claim.
