After a great fun activity using cardboard tubes to roll paint, we were left with some interesting looking cardboard tubes and decided we could use them for another craft. A few days later, the cardboard tube marble run was created.
Time: 15 minutes
Cardboard tubes (you'll need some long ones as well as a few shorter toilet roll tubes)
Paint if you want to decorate
Collect a selection of cardboard tubes.
Plan out your run, as the marble will start at the top and need to fall to different levels.
Cut a wedge out of the side of your first tallest tube and insert a half length of another tube. You'll need to make sure it's pushed right through so the marble drops onto it and doesn't fall all the way down.
Keep creating runs until you run out of cardboard tubes or enough height.
Play by dropping a marble in the top and watching it runs down the different tubes.
It takes a bit of patience to get it right and I was really impressed that my 4.5 year old persevered until we had the levels just right and the marbles running freely.