The Green Series of the Montessori Reading Scheme is when the children are introduced to phonograms made up of 2 or more letter sounds, these include the long vowel sounds such as: ai, ee, ie, oa, ue. They first learn how to read words containing the phonogram, then how to spell words using the Small Moveable Alphabet. They work through a series of activites ranging from wordlists, booklets, sentences and short story books. Once they are confident with the basic 15 graphemes of the phonemes they are then introduced to the different spelling (graphemes) of 13 phonemes (sounds) through the green envelopes. As in both the Pink and Blue Series the children are introduced to puzzle words which do not fit into the above scheme such as television, potion etc. These are generally introduced through word lists containing the same grapheme/phoneme.