I'm trying to get a handle on what this entails. If we get to the park early, do we sign up for an adult and kid to do it together? Or does the child do it while the adult watches? How long is the training? Is it next to impossible to get a spot? My 8 year old daughter would love to participate--the rest of my family, not so much, so I'm trying to figure out the best way to make it work (if at all). Thanks!