Module 2: Secondary Science – chemistry

Section 1 : Elements, compounds and mixtures

Theme: Probing students’ understanding

Learning Outcomes

By the end of this section, you will have:

  • used an activity to probe students’ understanding of definitions of elements, mixtures and compounds;
  • planned questions at different ability levels to help students observe and interpret a demonstration related to elements, mixtures and compounds;
  • used students’ drawings or models to probe their understanding of formulas of compounds and elements.


At the end of teaching a topic, teachers usually set a test or exam to find out what the students have learned. They are often dismayed to discover that it is not as much as they expected but by this time it is too late to help students. A good teacher will find out what students understand as they go along, and what the students are finding difficult and help them to make progress.

This unit has three short activities that will fit into your normal teaching about elements, mixtures and compounds and will show you how to find out what your students understand. Being able to recite definitions of key words like ‘element’, and ‘compound’ does not necessarily mean that your students understand what they mean. Don’t worry – the activities won’t prevent you from finishing the syllabus; they are fairly short and will help your students to learn. Once you have tried these activities, you will be able to adapt them when you teach other topics.

1. Teaching for understanding