ISSUES IN SOLUTION
It is very useful in this problem to have the students guess how many cans-worth of soda will fit in the box. These estimation skills are often underutilized in the classroom.
If the students work with `folder paper' and carefully score the edges to be folded with something that won't actually cut the paper, they can build the box and tape it together. And, if two students support the sides (because otherwise the sides would bow out), three cans of soda can be poured in (and quickly sipped out again using straws).
^*)