Appropriate grades or age groups:
grade 4 and up

Estimated time to complete this project:
2 days

Materials:
Popsicle sticks, glue. fishing scale, milk jugs. Saw horses or vise for measuring rig (details below). Safety goggles or similar.

What is the hypothesis of this science project? What does the experiment aim to prove?
What's the best shape of a beam to carry the biggest weight?

Instructions:
Have the kid make a beam one posicle stick long, with various cross-sections: T-shape, H-shape, Box shape, triangle shape. For a control standard, use one stick alone as a starting sample.

Placing the finished beams across a gap (we used sawhorses), hang an empty milk jug from the center and add water in quart increments until the beam breaks. You can use a fishing scale to weigh the load, or weigh the jugs on a bathroom scale before adding them to the load.

This can be fun to do in the driveway in warm weather, or a tub or shower in winter. The best beam my kid made held the weight of more than six gallons before a spectacular and fun failure. Goggles reccommended.