This lesson (1.2) is the second lesson in Chapter 1: Matter-Solids, Liquids, and Gases from Middle School Chemistry produced by ACS.
The lesson, which is outlined comprehensively in the lesson plan, follows the BSCS 5E Instructional Model. It begins with a series of questions as a way of helping students design an experiment to see if the speed of molecules is different in hot water compared to cold water. A well described experiment follows. The simulation that illustrates water molecules at different temperature is introduced to explain the observations in the experiment. The explanation is extended to explain why hot water takes up more space than room temperature water.
The website includes downloadable pdf documents for the lesson plans, the entire chapter, student activity sheets, the answer sheet for the activity sheet, and a student reader to be used at the end of the lesson.