I've made several fun toys and activities for kids using cardboard but nothing like these amazing projects. You'll be blown away by these 57 things to make using a cardboard box and cardboard tube. They are DIY activities, games, and imagination building props to encourage your child to play for hours. Cardboard Box City 1. DIY Cardboard Playhouses ~ Create an entire city block with these amazing playhouses. You can make trees and cars to complement the city. 2. DIY Cardboard Castle ~ Your little princesses will adore playing make believe in this fabulous castle! And, you can make