I am personally ok with a couple of scenarios. 1. one deck and guy in the whole celebrating....2... the whole team but they better give them five and hustle back to the dugout. I think the guiding principle should be don't be disruptive to the continuity of the game or show up the other team by celebrating too much.
Our kids go to the plate. It's a game. It should be fun. I hate the tick-tick boom stuff, we don't do that. Just kids slapping their teammate on the helmet. Surely 12u is not too old for that.
The pros celebrate on any walk off hit or home run, what is wrong with kids celebrating hitting a home run, especially the kid who hits his first or for the kid that no one ever thought would ever hit one, At 12u and under, celebrate all you want. Have fun with it!
Seriously, they are 12 year olds - they stii love snow cones and playing on the playground at the park - let them have fun and celebrate as much as they want .... It's only a game!
Most of these 12 year olds play the game for a different reason than many of us adults realize. They still play to have fun and because they love the game. You take the fun out and for a large majority, burn out will be just around the corner!
I hate all the Tick Tick boom crap and would never let my team do it but the bottom line is if you don't want to hear it then don't give up the home run. Fact is if your kid stays in competitive sports he / she is going to hear it and better get use to it. We play teams from time to time that have obnoxious coaches players and fans but who cares, shut them up with your play on the field..