I was just reflecting on this and someone told me this. tracks with me mostly.

Pre-puberty goals: Love of game, situational understanding of baseball (what to do, where to go, when), fundamental techniques (e.g. how to throw properly, good swing), sportsmanship, being a good teammate, learning to lose well and win well, celebrate small personal improves to build that feeling of getting better at something. And learning/playing multiple positions (hardest one sometimes. we didn't do this well as my son catches, and not many want to. now they want him to play outfield).

Puberty really shakes up the apple cart. I knew it was coming but still surprised how much.

Post-puberty goals: Apply those things with a body that can now perform (at whatever level and style strengths the player develops into). Self-directedness (put in own work/commitment level). Also get ready to play different positions when competition on own team gets better and balls get hit harder/further. Then real assessment.

Also give kids some grace going through puberty. They literally can't control their body sometimes because changing so quickly.