OO (zoo) Sound Word List
The /oo/ sound has nine spellings, oo (soon), ew (chew), ue (blue), u-e (rule), o (do), ui (fruit), ou (soup), u (truth), and ough (through). This makes it one of the more complicated sounds to spell accurately. In addition, most of the spellings represent other vowel sounds that must also be learned which complicates the reading process as well.
Of the 7,000 words in the database constructed from a popular children’s dictionary, 111 of them are one-syllable words in which the vowel sound is /oo/.