A beach, forests, wetlands, and the potential to spot wildlife; Lake Sammamish State Park has it all. And people have been appreciating what the area has to offer for generations -- the land around the lake is culturally significant as a gathering place for several Native American tribes.
Find peace on the Homestead or Issaquah Creek trails, forested routes in the northeast corner of the park. This salmon-bearing creek can be an educating (if pungent) diversion in the fall when the salmon are spawning.
Or take a tour past the soccer fields on the Orchard Loop. Tibbetts Creek trail follows (yes) Tibbetts Creek for half a mile to Tibbetts Beach, and the Joggers Loop encircles the softball field near I-90.
Because the park is close to the cities on Puget Sound, it's a good half-day destination for when you want to get out but don't quite have a full day. That also means you'll share the trail with plenty of other folks.
If you and the family want to add another activity to your visit, you can bike, geocache, go birding, or even rent kayaks or paddleboards at Tibbetts Beach. If it's more hiking you're after, consider heading next door to Beaver Lake Preserve, where WTA volunteers have done some trail work in the past.