Andy Chandler-Grevatt explains how you can develop your mental map of chemistry and improve your assessment of your students’ needs

An illustration of students in a classroom discussion

Source: © Claudia Flandoli

To effectively understand where students are in their knowledge and understanding, you need to develop a mental map of your subject

Classroom assessment can be seen as the skill of a teacher to understand where a learner is in their knowledge and understanding, and the know-how to get them to the desired level of knowledge and understanding. Without direct understanding of your subject, you are unable to assess your students’ needs and intervene.

There are various ways to reveal and develop a chemistry teacher’s mental map of their subject; I will describe an approach I use that works for a concept or experiment. Trainees and teachers, who are looking to improve their assessment literacy, can use this method to develop a fuller mental map of their subject, and understand the terrain of chemistry they know in terms of the curriculum and beyond.

Develop your mental map

Step 1. Select a concept or experiment

As an example, let’s take the displacement reaction between copper sulfate and magnesium, which is part of the curriculum for students aged 11–14 years.

Step 2. Consider or discuss the following questions

Where have we been? What is the prior knowledge and understanding required?

Where are we now? What is the new knowledge and understanding taught?

Where are we doing next? Where does this knowledge lead to?

Step 3. Write down your thoughts

Write your thoughts down in a table (an example is shown below) or draw a mind map.

By following these steps, you consider what you know and what you expect the students to know when you teach a specific concept in chemistry. Some of the responses I have received for this activity are shown in the table. Remember this is for 11–14 year olds; different stages of chemistry for the same experiment will have different expectations.

Example of responses to the prompts:

Where have we been?Where are we now?Where are we going next?

Metals and non-metals

Particles: atoms, elements and compounds


Chemical reactions in general.

Other specific chemical reactions, eg oxidation, thermal decomposition, combustion

Word equations

Reactivity series

Displacement reactions

Applying reactivity series

Description of this specific reaction

General word equation

Specific word equation

More examples of displacement reactions

Application of reactivity series in other contexts

Symbol equations

Improving your terrain of chemistry

There are three effective ways to develop your mental map of chemistry topics: collaboration, reading and research, and teaching experience.

  • Collaboration. Doing this activity with a colleague or as a department is beneficial because you can learn from each other; you can compare mental maps. Together, you can see gaps in your terrain, discuss and develop them. This simple activity to reveal and compare mental models is one of the most powerful to improve this element of your assessment literacy.
  • Reading and research. Keep reading textbooks, popular-science books and science news websites to build your mental map. Add facts, anecdotes and context to your terrain of chemistry. Increase your body of knowledge so you know it inside out.
  • Teaching experience. The more you teach, the more you will understand how the curriculum knowledge fits together and the more you will develop your mental map. As you observe a learner who is lost, you can check where they have been and identify what they’ve missed on their learning journey. How alike is your map of chemistry to their map of chemistry? What needs to happen to align them?

Developing your assessment literacy

The focus on and development of rich subject knowledge is an essential element upon which to build your assessment literacy. By developing your knowledge, applying it in the classroom and critically reflecting on your mental map, you will improve this element of assessment literacy.

The next article in the series will look at knowledge of misconceptions and mistakes — to identify potholes of misunderstanding and mountains of conceptual demand on our subject mental map.

Andy Chandler-Grevatt