You are about to read a brief illustrated story and answer a few questions about it. The entire exercise takes about 2 to 5 minutes.

We ask for no name, no email address and no identifying information. Your response is linked to your class code and to a short-lived session key your browser holds, which stops the same browser answering twice — so the data is pseudonymous rather than strictly anonymous. Nothing in it points to you by name.

Participation is voluntary. By clicking Start you confirm that you are willing to take part.