1 Cambridge english : Key for Schools Key english Test (KET) for Schools Computer-based sample test This computer-based sample test allows you to see what a full computer- based Cambridge english : Key for Schools exam will be like, and shows the types of questions that will appear in the live exam. You will need to use the Firefox browser, you can download Firefox for free here. Once downloaded, open Firefox and use the links below to view the tests. Watch this tutorial before you try the practice test below, this will help you understand what you need to do. Listening Reading and Writing Check your answers as you do the test once the test has finished you will not be able to check them.