I just recommend when you start anything from the block have them starting in a position where they're already kinda under the bar (not sure how to describe but basically I've seen it where the coaches are having the kids start it with their body in a cast position, just on a block, and that doesn't really help overall. Set it so their toes are down and their should a are slightly back, then have them drop. I like to spot from the bottom and push their shoulder rather than yank them up unless they can already do it, because you can yank anyone up regardless of their technique if you go that route. Also being under the bar lets me control their drop. But you have to make sure they can safely shift around first without collapsing. So a few months before have them start doing the level 3 straight arm backward roll from laying down off a slightly elevated surface above a low bar.