Although seemingly dead simple, the beauty of this activity is that it generates the next logical need-to-know again and again. Here you actually GIVE STUDENTS THE NUMERICAL ANSWERS, at least one section at a time. Then, ask them to complete the following section. They will be left wondering which way to go for the following questions: what's the difference between a molecule and a compound (atom/element)? How to count diatomic elements? How can letters and subscripts represent atoms? You bring them up to the edge of their knowledge again and again. This is intended to be actively guided step by step by the teacher, but slowly. After students realize they do NOT know what you're asking them, they will be truly ready for definitions, the how-to's, and the meanings, not just the counts or "answers." This should NOT be used as homework.