I loved the days when my kids could take just about anything and convert it to something fun to do. For example,

giant-boxes-on-board-screwed-into-two-sets-of-skateboard-wheels +  gentle-incline => tandem go-cart race

On your mark…

And awaaaay they go…

I probably thought this was horribly dangerous. If only this had remained the pinnacle of risks that my now 19-year-olds would ever undertake.