Are you visiting or live in the Melbourne, FL area...do need something to do with kids?
Try the Andretti Thrill Park!
From amazing attractions like the Super Speedway, the F1 Track, the JR. Indy Track, the Andretti Challenge, the Wave Rave, Mini Golf, Laser Tag, Arcade, Batting Cages, Mini-Bowling and more. FYI...some of the rides do have height restrictions so go to the website and make sure your kids fit the criteria...http://www.andrettithrillpark.com
They charge by the hour or day to use the attractions (you can also ride the individual Andretti Challenge for $14.95) and they often run specials.
Here is a link to the specials they have online: http://www.andrettithrillpark.com/specials.html
They offer some food options that are not totally awful (Pizza, subs, chicken, etc...).
We love this place. My suggestion...by a three hour unlimited attractions pass that includes a $10 game card (on sale on the link above for $31.95). That is about as many rides and games you will be able to stand...lol. It will give you enough time to try out everything and decide what you want to ride or play the next time you come back :)