Directions 1. Review for the quiz. Ask students which main ideas about atoms and molecules they remember from the Systems and Scale unit. Remind students of three important facts about atoms: Atoms last forever (except in nuclear changes). Atoms make up the mass of all materials. Atoms are bonded to other atoms in molecules. Review what students learned about molecules in food and how to read nutritional labels. Remind them that they can identify molecules with chemical energy by their bonds (C-C and C-H). Remind them how to read nutritional labels to find different molecules, to find calories, and to find if the food has chemical energy. 2. Have students take the quiz. Pass out one copy of the 2.3 Molecules in Cells Quiz to each student and give them 10-20 minutes to take the quiz. Tell students that they will be graded for their answers on this quiz. 3. Discuss their answers to the quiz. You could have students grade the quiz themselves as you go through the answers with them. Discuss any questions that many students had a difficult time with. This should serve as formative assessment for you as a teacher to identify which concepts students are still struggling with.