Building A Bridge For A School Project

Phillip my 4'th son was to build a bridge for a school project, They was standards that the bridge had to live by, lenth, the inside size was to be large enough to pass the teachers koffee cup, and it was to be able to withstand 10 Lbs of stress in the center... We stress tested our bridge at 20 Lbs. Father's were allowed to help in this project, and we got high marks on our bridge of wooden sticks and glue...