Generally speaking you won't get any baseball related deductions unless you are in the trade or business of coaching/playing baseball. This means if you are a coach you must be getting paid, or if you are a player, you must be a professional player (getting paid).
As a coach for a team run by a non-profit, or even a parent of a player on a non-profit run team, you might be able to deduct some voluntry payments to the organzation or expenses incurred by you on its behalf as chartible contributions. This does not include your son's fee to play on the team, to buy your son a glove etc.. However if you make a donation and there is no quid pro quo and you properly document, you can get a deduction....just like church etc..