Built a treehouse with my kids this summer and it was the best decision ever

Spent about 6 weekends building a simple treehouse in the big oak in our backyard. Got pallets from work, used old lumber, made it safe with railings. Cost me maybe 150 bucks total. My 6yo and 9yo helped with every step and learned so much about building. Now they spend hours up there reading, playing, just hanging out. Wife loves it too because they actually go outside. Highly recommend if you've got a good tree and some basic tools.