An easy, accessible way to start your ToK course. Students view the SmartBoard Notebook file and place the various statements, all of which begin with "I know..." on a "Certainty Graph" ranging from 100% certain to highly doubtful. Students share their choices and must defend them to the class. Students are then asked to discuss what criteria they apply to a knowledge claim to decide its certainty. This could be done as a writing assignment too.Students can do this activity in groups or individually. The file is easily convertible to PDF format should you choose to use this as a handout.