For our LEGO Set assignment, we decided to create a slingshot.
This creation requires no 3D printed LEGO piece, since we found that none of the pieces we needed printed were required.
We have decided that we will use this slingshot, since its both simple to make & powerful for hitting targets.
Following these building instructions, while placing a rubber band between the LEGO pieces at the top, you will have a Slingshot.