At that age, my kids were happy at KAH summer camp, which is one of the cheaper options for full-day coverage. It had a good mix of activities, plus field trips and swimming once a week, and was fun and easy to handle. Here's the list of locations and info:
https://www.kidsafterhours.com/summer-camp/summer-camps/day-camp/
A similar option might be the summer camps run by Bar-T, either their cheaper kids camp (held at local schools, similar to KAH), or their "Ranch" or "Mountainside" campuses:
https://www.bar-t.com/summer/