Show slide 13 of the PPT and ask students to compare their results to the results for Ms. Angle’s class.

- Explain to students that the data from the video (or from Ms. Angle’s class) showed that the potato lost 0.66 g and the mealworms gained only 0.37 g. So overall the system lost 0.29 g. Remind students that atoms are forever, so this mass must have gone somewhere. Students may have some ideas about where the mass went. Tell students that you will discuss this missing mass later in the unit.

The remainder of the unit is based on the assumption that your class results are similar to those of Ms. Angle’s class and the Mealworms Eating video. If your class results are significantly different for any reason, after a conversation about why that may have happened, decide whether to have students conduct the investigation again or to refer to Ms. Angle’s data as they work through the remainder of the unit.