An old adage on the subject of memory claims that we retain 10 per cent of what we read, 20 per cent of what we hear, 30 per cent of what we see - and 50 per cent of what we hear and see.
It's not clear how much, if any, science lies behind this. But it's true that we seem to remember a large percentage of anything we have said or experienced ourselves. (Particularly if that experience hurt.)
Imagine that you had a leaking bucket and that 90 per cent of the water ran out when you attempted to fill it. You'd probably only fill that bucket once before you began experimenting with ways to fix it.
The same is true for your students. Getting them to research projects - whether these are scientific, academic or practical, such as finding a solution to a problem that affects them and their peers - is effective on a number of levels.
First, you are giving them ownership of a subject or issue and asking them to discover the best way of dealing with it. Second, they are likely to come up with fresh ideas. But the last benefit is the most powerful: you are teaching them how to listen to, and digest, the thoughts of others while balancing the evidence to find a way forward.
They should emerge with improved comprehension and communication skills that will take them through school and university and be an aid in the workplace. But how are teachers expected to do this? And how do you choose a project that will engage students?
At the simpler end of the scale, there are the young students who campaigned to change the way children with packed lunches were forced to queue for up to 15 minutes before they got into the lunch room. They employed scientific means of researching the best solution. At the other extreme, we have sixth-formers engaged in academic research on multiple sclerosis in association with a local university; a project that has real potential to help people.
The secret appears to be less in the subject, however, than in tapping into students' sense of comradeship, competitiveness and desire to work things out for themselves. Most students enjoy a challenge - and they love telling others what they have learned. And passing on knowledge is another, almost guaranteed, way of remembering things.
Jo Knowsley is acting editor of TESpro, email@example.com @tes.