Paper horse that walks! https://frugalfun4boys.com/paper-horse-that-walks/

Bird kite - http://krokotak.com/2017/06/simple-bird-kite/

THE ARTFUL PARENT

https://artfulparent.com/12-kids-art-games-for-fun-and-creativity/

https://artfulparent.com/12-kids-art-games-for-fun-and-creativity/

Walking silkworm - https://youtu.be/v9Z9wt7vO80

Lego Pets (and other activities) - https://frugalfun4boys.com/lego-pets-building-instructions-dogs-cats/

Lego gravity rollers - https://frugalfun4boys.com/lego-gravity-project/