The Animated-Alphabet™ flash cards come in three colors. The green cards are for the 26 letters of the alphabet. Each green card has an upper case letter on the front along with an alphabet character and a lower case letter on the back with its alphabet character. The yellow cards are for spelling patterns that represent only one sound (ch, sh, ai, oi, etc.). The yellow cards display the letter pattern along with an alphabet character on the front and a word list on the back. The blue cards are for letters and patterns that represent two sounds (c, s, ow, ea, etc.). The blue cards have a letter or spelling pattern displayed on the front along with two alphabet characters. On the back of each blue card is a vocabulary list for each sound represented by the letter pattern.