A Building Challenge

My son LOVES to build.  I am constantly trying to find something to challenge his building skills.  We were playing with old Cd's the other day (that's an upcoming post) when it struck me to get some paper towel tubes and put those and the disks with our construction equipment (just a fancy way to say blocks, but this is the terminology I use with my kids to hopefully encourage them to think bigger and outside of the box).  Anyway, his eyes lit up as he recognized the challenge.  He grabbed the egg cartons, (another piece of "equipment") and this is what he built.  What unconventional building materials do you have in your construction equipment?

r

I love how the paper towel tube fits right on the egg carton!  So cool!