North Highlands is a town about 10 – 15 miles northeast of Sacramento. It grew with the development of McClellan Air Force Base (now McClellan Business Park since the Air Force Base was decommissioned). It is an appropriate place to go for a good day of space, science, and discoveries!
First check out the Discovery Science Museum. It not only has lots of great hands on activities for kids, a few small animals to observe, but offers activities such as star shows, wild animal shows, or crafts throughout the afternoon. (The star show is for kids over 4 years.) There are 14 acres of woodlands behind the museum to have a brown bag lunch and run off some energy. (Cold drinks available for purchase in the museum.) Since this museum opens at either 10am or noon, depending on what month you visit, I would suggest bringing a bag lunch or snacks to eat outside. There are benches there and its a nice area. There are, however, a few places nearby to get food, though I forgot to write down the specifics when I was there.
For your next stop, go southeast on Auburn Blvd toward Watt for .2 miles. Turn right on Watt for two and a half miles, then turn left on Freedom Park Drive. This takes you to the Aerospace Museum of California. Explore full scale military planes and helicopters, or ride in kid flight-simulators.
Next door to the Aerospace Museum is Freedom Park. This offers a playground with a rocket shaped play structure. There are two areas for kids to climb, each appropriate for different aged kids. The park around it is nice and offers lots of space to run off extra energy.