In this activity, learners construct a small "air cannon," and use its airflow to put out a candle (lit with the help of an adult). The "air cannon" is an empty salt carton with a plastic bag rubber-banded around the cut-off bottom, though other containers could be tried. Learners can submit online the distance from the candle the air cannon successfully blows it out. This activity should be done in a fire-safe environment.