Here is a worksheet on the Greek word root chron/o. It means, as you probably already know–but your students may not know–time. It’s an extremely productive root in English; as this worksheet shows, chron/o is at the base of a number of words that educated people know and routinely use: chronic, chronology, synchronize–this list could go on at some length.
If you find typos in this document, I would appreciate a notification. And, as always, if you find this material useful in your practice, I would be grateful to hear what you think of it. I seek your peer review.