Description Max's Fez . An elf has stolen Max's fez! How will Max get it back? Is Willa Bad? . Willa seems to be a wicked witch. But is she really so bad? The phonemes /x/y/z/zz/ are featured in this title. In Level 3 - Yellow books, children build on the letter-sound combinations learned in levels 1 and 2. They learn consonant digraphs (sounds made up of two letters together such as 'ch' or "ll") and long vowel sounds (such as 'igh' or 'ai').