Ob-Scertainers are closed in containers that have fixed shape inside with a small marble. The goal is to have students try to figure out the pattern inside the container just by moving the ball around. Students should make observations on the worksheet while performing the experiment. The worksheet allows students to sketch what design they believe is inside the container and draw conclusions based on the movement of the marble. After students have done their best to guess what is inside, they should then open the container and sketch the actual layout of the container. The comparison of the prediction and the actual are always interesting, but students should understand that we cannot completely determine the pattern inside without it being open. However, we can get an idea. We don’t always have to see the object completely to determine some of its properties, and we can use previous knowledge to make inferences about things we cannot see.
The purpose of this experiment is to show students that they don’t have to see everything to know it’s there. (Just like atoms!) This activity in itself is the perfect introduction to a conversation about atoms and how they are everywhere but we cannot see them. They make up everything around us! I think students would be frustrated with the idea that they aren’t able to see what’s inside the containers and try to pry them open. I think younger students would also find difficulty in trying to conceptualize abstract shapes that they aren’t familiar with. I would try to find containers with basic shapes to ease the frustration and give students something a little more familiar when introducing a new topic.