As a First Grade teacher I can tell you that Color Coded Sight Words (Dolch) save my life! When a student asks me how to spell the word "like" for example I can say "It's on the word wall, under the letter L and it's pink." My kids do such a better job finding the words on the word wall and helping each other spell words.
This product includes all of the Dolch Words.
First Grade: Green
Second Grade: Blue