This second set was just released and wasn't around when I taught my oldest to read. Although she did fine without it, I thought that the additional practice on this basic level was very helpful for my son (who has just finished this second set). Like the first set, the stories are designed entirely for the purpose of practicing beginning reading skills by introducing sounds in an intelligent order. The stories are very simple and usually quite silly. This set does introduce several two-letter phonograms - "ar" (book 3), "aw" (book 3) "ow" (book 4), "ou" (book 7), "oo" (book 12).