-Pitch a tent in the backyard and have a campout (save money on gas to drive to a campground, campground fees, and indoor plumbing

)
-Nature hike
-Bike ride
-Splash pads or run through the sprinkler
-Sidewalk chalk or paint
-Turn the kids loose outside painting with water and a paintbrush
-Library (free crafts, story time, and other events)
-Bake together
-Lay down outside, look up at the clouds, and come up with different things you see in the shapes
-Paint (finger painting, blow painting, marble painting)
-Sand art (I've found all kinds of sand art supplies in the Target dollar bins and at Michaels)
-Board Games
-Tag, Hide and Go Seek, Simon Says