In this activity, students learn about the mole. In section 1, students learn what a mole looks like for different substances. In section 2, students learn how the number of protons and neutrons in the nucleus determines the molar mass of an element by comparing individual isotopes in a PhET simulation..
Face to face professional development provides the opportunity for teachers to learn from and share with other teachers. This post provides an example of one of the many great ideas that I have learned from other teachers.