In groups of 3/4 make the tallest tower using only spaghetti, and mini marshmallows.
20 Pieces of Spaghetti
20 Mini Marshmallows
This is the resources per team.
We have 18 Cubs and therefore used a lot more than only 20
Give the groups there resources and 15/20 minutes and let them come up with their own designs.
at the end you could mark them on design, height and strength