Catapults for Kids

I just love using STEM in my science and math classes.  We had just finished learning about simple machines and went into building a catapult.  The students had their supply list and were given a limited amount of time to research on the computer.  They had to sketch out their designs and were not allowed to look back at the computer the next day.

Here is the list of materials that they were allowed to use:

• Large and small craft sticks 10 altogether
• Rubber bands 6 or less
• Plastic spoon 1
• Binder clip 1
• Plastic cup 1
• Clothespin 1
• glue gun and masking tape

Grouping Tip:  No more than 3 in a group!!!  It cuts down on problems.  All kids have a chance to use materials and have a say.

Here is a video I like to show my students before we start.

Link to a recording sheet on Scholastic

Great resource and engineering website with sheets: Teach Engineering

Day One:  Imagine and Design

Here are my students researching designs.  I love listening to their ideas.

 Day 2: Building

The next day we started building.  My students really had to work together and collaborate to make their designs come to life!  I had one group that wanted to give up but they persevered and got the catapult to work.  Problem solving in action.

Building Tip:  Have a glue gun on hand!!!

 I found this design on the internet with zip ties!

 Day 3: Test and Rebuild

The students have a chance to test their catapult and make adjustments as necessary.  You might want to limit the amount of times they can test.  Hint for kids: I do tell the kids that the plastic spoon will bend and lose its strength and some will break,  they really need to support it. (I learned from last year)

 Day 4-5: Test for Distance and for Accuracy (Target)

Each group had three trials for distance.  We recorded on a table.  Then ranked in order.  Great place to reinforce some math.  Record in ft/in or m/cm.  Put on a graph.

Each group also had three trials for accuracy.  I made a target with points.  We added the totals of the three.

 Here is how you can bring the A into STEM.

Have the students decorate their catapults.