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These worked perfectly for my 1.5 year old. I filled sections of an ice cube tray with different colored watercolors and gave her some cotton make-up pads to drop colored water on. The faults of these droppers actually ended up being features for us because she doesn't have the motor skills yet to actually use them correctly. She just stuck the end in the paint and kind of pounded it, and it sucked up a couple drops. Then she put it on the cotton pad and pounded it again and the drops fell out. However, I can see them being hard to control for a child who is just learning how to use them correctly, because they will drip if they are held with the end down.