I made these color coded labels for my five year old son. He already knows his colors but I wanted to expose him to some sight words so I thought - Why not use colors? We turn it into a matching game, I lay out different objects on the table and he uses the label to tag each item with the name if its color. He is able to do it not because he can read the words but because each label comes in the color that it represents. But I think it's a good idea to expose children to words in context, even if they can't read them as yet.
If you would like to try them out with your students, it's available as a free download pdf file from my TeacherspayTeachers Store. Click right here to download it for twelve colors!