Young Family Cup!
Marshmallow Catapult ~ These would be so fun to create during force and motion lessons!
Lawn Jenga, oh how fun! And so easy to make, just cut 2x4s
Minute to win it party - so many fun games
Looking for a fun outdoor game? Try making this jumbo Jenga game to play on your lawn. via Instructables
Yarn and tape a hallway for a "laser obstacle course". That will keep 'em busy for a couple of hours.