Here are two catapult models we developped specifically for 8+ and 12+ kids. Just print it or have fun doing it with your kids ! 8+ : -catapult final : https://www.3dslash.net/thing.php?hash=8d072d461d86c8af0ee091f82970d856fcd52841184df599a73ae33394c746c2&filter=3,0,0,0 -starter file : https://www.3dslash.net/thing.php?hash=f590e1b7467a7911fb05a8be4f773a4539eda8202030e0c8b6a74d7c0a191605&filter=3,0,0,0 12+: -catapult final : https://www.3dslash.net/thing.php?hash=7d25e141f5d4135a7db05176d1a152f8f86c5f8d6cd786e3a1d1d6161b679ee4&filter=3,0,0,0 -workshop document :http://fr.slideshare.net/3dSlash/3-d-slash-catapult-how-to-run-a-3d-modeling-and-3d-printing-workshop-for-812-years-old-kids