The IF area does have an Edwards theatre (14 screens I think), Little League, there's a mini-golf course with other attractions up the road in Rigby (less than 30 miles), YMCA, several city parks with the slides, swings and the like, most every other family has a trampoline in their yard, there's also Teton Spectrum has indoor go-cart type track with arcade games. In winter at Tautphaus Park there's an ice hockey league, not to mention cross country skiing at a few parks and trust me kids around here start skiing and snowboarding at a young age.
We do have a few museums and a city library downtown and then there's the greenbelt that is a path around the Snake River and the falls in downtown IF. You can bike it, hike it or blade it (for us oldsters, you can walk it too

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Oh almost forgot, we also have two drive-in theatres and a minor league baseball team!
Just about forgot that we have a smallish amusement park connected to the zoo.