J.W.
there is a t-ball league for ages 4-7 here in lakeland. i already called and they said they are still trying to get enough people to start a team so they took my name and number and said they'd give me a call when they were ready to start registration. the webpage is
http://www.lakelandgov.net/Parkrec/recreation/recleagues/...
also, the ymca offers gymnastics classes for 4 year old boys and girls. you can give them a call and ask them about it.