100 Rolls of Toilet Paper, What to do with the leftover roll?

Now that you have 83 rolls of the big question is “What are you going to make with the cardboard tubes?” 

Make something interesting out of those leftover toilet paper roles: castle, telescope, binoculars, marble race track, use your creativity!  If you need a little help I have listed some 3rd party website that have some STEM or craft related ideas for those leftover toilet paper rolls.