Picnik.

butterfly-life-cycle
Originally uploaded by Miriam346

This is the picture that I re-sized and cropped on picnik. It was easy to use and did the job. I would be able to use Picnik as a tool for editing pictures to use in class. For instance if I found a picture that would be great to use as an educational device, but it had other images that I wanted to get rid of, I could crop the picture so it only had the image I wanted to use and re-size it accordingly.