Demonstrations were used to focus on and explain Newton's first law. These included showing a cart's motion at rest and determining what is needed to make it move forward. It also included the cart moving forward and determining what caused it to stop. The demonstration of a coin held over a paper cup on an index card, with the student trying to have the coin drop in the cup by removing the index card was used to also demonstrate the first law. The First law was stated based on the information gathered from the demo. Once stated, a demo was performed to show that if a cart with a small doll sitting in it was suddenly pulled forward, the doll would fall backward. The same cart with the doll was rolled at constant rate and stopped abruptly by a wooden block, showing that the doll would launch forward. Rubber bands were used as a seat belt to tie the doll in place, and the crash repeated, demonstrating that the doll did not fly forward, strengthening the need for the use of seat belts. Finally, the force needed to just move the cart was measured, and then extra masses were added to the cart and the force measured again. The affect of increased mass on inertia was shown. Newton's first law was written in a statement form.