Much as I'm not a board coach but was once an U12 nipper ... popping ("sitting") a wave is bit hard at that age but can work. Small broken or unbroken ... pick the paddle rate UP before wave hits and lean back a touch on way over. Not freeze, stop, hang on and get washed back. For the big waves, go the eskimo roll. Most of what you see here works on a nipper board.. Practice and have fun!