What a great idea. Make your own I SPY game with a VOSS water bottle. You fill it with rice and drop in little things to hide and then make a list of everything in the bottle for the kiddos to find. This is a great travel activity.
30 things to do with kids such as indoor camping - frisbee tic-tac-toe - homemade bubble recipe - DIY coloring case (easy handmade gift) string laser hallway game - how to make a solar oven with a pizza box to roast solar s'mores - night games like glow-i
DIY Dyed Rainbow "Grimm" Style Wooden Blocks (unfinished wood blocks dyed with liquid watercolor-- looks VERY easy and affordable. Just note that it is not baby-proof bc the dye is not 'set' and will come off with water (ie slobber))
11 DIY Ideas To Keep Your Kids Outside This Summer