Just not long back from
Icmeler and visited all the places that Blondie has mentioned. I will also recommend Maya Restaurant, opposite where Za Za's Havana bar was last summer. It has a small play area with basketball and football goals and a couple of toys for younger kids, don't know if your kids will like it as they are a bit older(apart from youngest) than my son who is 3,but he loved it and the meal was lovely too.
There is also a place up near the Nazar Café,can't remember what it's called but it has trampolines, bouncy inflatables and some games for older kids, shooting games, table football, basketball etc and the prices weren't too bad. Token for trampoline was 2.5 lira for 10 mins,same for the battery operated cars that they have where you drive round the track etc.
Lots of places have pool tables,play stations and wii's the older ones can play and the Icmeler restaurant has pool,crazy golf and a good play area with chutes,swings etc that would interest the wee one.