This is such a great project - it's cheap, recycles plastic, you don't have to touch the food and it's really easy to make.
I used a marker pen for the decoration because it won't come off or get damaged if the scoop is washed.
There was some concern over chemical residue which I thought about too but laundry detergent doesn't have very harsh chemicals in it or otherwise the clothes would be damaged or everyone would react to clothing on their skin. As long as you clean it thoroughly it is safe.
Thank you to KMOM14 and Kaboose.com!