Display the Gas Has Mass Task Cards. Read through the method for each activity and ensure that the students understand the tasks.
Divide the class into four groups and assign a task card to each group. Assist the students as they gather the required equipment to set up a work station for each task card.
Allow the groups approximately ten minutes to work through the first activity, then have them rotate through all of the stations. Monitor and support the students as they complete the activities.
Gather the class back together. Review the tasks and invite the students to share their results. Check for misconceptions and discuss any discrepancies.
Review the lesson’s statement for investigation: Gases have mass and volume. Discuss whether the statement is true or false based on the information presented and the findings from the activities.
Encourage the students to think about the slime created in Lesson 1. Discuss whether or not the slime could be a gas. Encourage the students to refer to the observable characteristics of gases when making their judgements.