intro:
Teaching kids about science can be fun! It is great to bring excitement into more serious subjects. Building Bridges is fun way for children to learn hands-on about weight and gravity. Students will measure weight in tangible terms.

set up ideas:
Research and explain some of the most famous bridges in the world. Share information like how old they are, where they are located, how much weight they can hold, etc.

let's get started

Show the children a reference picture or pictures of different bridges. The materials needed are books or large blocks, strips of heavy cardstock paper and weights (a large quantity of pennies or weighted counters work great.)

step 1
Talk to the children about bridges. Explain that the structure of the bridge determines how much weight it can hold. Help them to understand the importance of a sturdy structure.
step 2
Pass out the materials and help the children build a simple paper bridge between two books or blocks. They can use the pictures of real bridges that you found as reference.
step 3
Have the children count as they stack pennies or weighted counters on the bridge until it falls. Keep track of the number that was stacked.
step 4
After the bridge falls, have the children suggest ways to rebuild the bridge so that it can hold more pennies or counters. Encourage children to brainstorm in groups.

Go over the weight of each item stacked and why the bridge fell. Explain the different ways the bridge could be sturdier. Ask groups to share what worked most for them. Ask them to think about other structures that hold a lot of weight like buildings, cranes, dams and more.
Tips and Tricks
Once your students understand weight, further the lesson by going over the way weight is pulled down by gravity, and the rates at which they fall. Drop a penny and a paper at the same time. Point out that both fall to the ground but a penny falls faster because it is heavier.