Kennedy Space Center if you are willing to drive!!! There is also the huge Ron Jon surf shop at Cocoa Beach if you like shopping. I heard Blue Springs state park has manatees, also a bit of a drive, but haven't been.
Gatorland I've heard is pretty cool. Legoland is neat(I have not gone) that some age groups love. We always have done a beach day and visit family we have that live there. Some of my most recent trips were moves down. I miss it now that I had moved back to AZ. If he's into cars you may check out Old Town http://www.myoldtownusa.com/ Weekly car shows and some other shopping and rides and stuff(small).