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Take a moment to consider your students and what they might think about acids and bases.

What initial impressions do students have of acids and bases?

Students may be familiar with the idea of acids in the wider world and some ideas about them being corrosive. However, their notions of acids can be based on over-exaggerated portrayals of acids in cartoons, films and other media.

How can I dispel the fears of my students if they are very apprehensive about working with acids?

You may find that some students are nervous about using acids and need reassuring. They might have the impression that an acid will make a hole in their hand a bit like the hazard symbol. One approach is for the teacher to demonstrate that they can wash their hands in dilute acid. Of course, no hole has appeared but the next thing students see is the teacher rinsing their hands carefully in water. You can try to allay their fears while keeping a healthy respect for safety in the classroom.

Conversely, if some students appear to be overly blasé in their attitude to practical activities, you may wish to go to the opposite end of the scale and demonstrate the dramatic effect of adding a few drops of concentrated sulfuric acid to some sugar or a paper tissue.

Educational research reports that students are less familiar with bases. Is this your experience?

Educational research suggests that students may be far less familiar with bases and they may be surprised to realise that some bases are even more corrosive than acids. Bases (or alkalis) are often neglected.

What ideas might address some of these difficulties?

Alkalis and acids can be introduced equally from the outset. This can be done via a range of activities, for example by making links with everyday chemistry in society and the wider world, through practical work, class discussion or other activities.

For example the question ''Which are the most dangerous, acids or alkalis?' could be a topic for discussion.

A practical example is provided by this simple classroom activity where bases have equal emphasis from the start and students are encouraged to make their own observations. This 'microscale' experiment has the key advantages of being quick and easy to set up, promotes quiet working and making observations by students, and it is safer, 'greener' and more economical due to the small amounts of substances used.

These are some starting suggestions to consider – further ideas are outlined on the next few pages.