I use sight words according to my units (you can use dolch words or whatever your school uses) and I put 8 words on each arc of a big rainbow I have in my class. I made a cloud for each of my students and put his or her name on the cloud. I teach 2 words a week, so after 4 weeks when all the words on an arc are taught I test my students. If they can read all of the words in the arc, they receive that color raindrop for their cloud. If they don't, I test them every week until they pass and can move on to the next arc. Students are very motivated to learn all of their sight words and earn their raindrops.