While cooking dinner yesterday, I had a sudden inspiration for the stalks of the broccoli that I had cut off to discard. I looked at them, and saw that they were such interesting shapes, and thought that Simon might really like stamping with them. I poured a little paint out for him to dip into and spread some sheets of paper on the table. He immediately knew what to do and had a great time.
Next time you have stems chopped off from vegetables, perhaps you should consider using them for this type of kid-friendly printmaking.