Yes — "buy" is a Third Grade sight word. Its "uy" spelling for a long "i" sound is rare in English, and it sounds identical to "by" and "bye", so it's memorized rather than decoded.
We went to the store to buy milk.
"Buy", "by", and "bye" are homophones — same sound, three completely different meanings and spellings. "Uy" is an especially uncommon way to spell the long "i" sound, appearing in very few other English words, which is exactly why "buy" needs to be learned as a distinct, memorized shape.
Teach all three homophones together — buy, by, bye — with one clear example sentence each, so the differences in meaning anchor each spelling.
Word Wizard teaches "buy" with Flash Cards, Listen & Pick, Spell It, and Write It — four game modes that turn repetition into play.
See "buy" with its picture, syllables, and example sentence — with native audio.
Hear "buy" spoken aloud and pick it out from similar-looking words.
Build "buy" letter by letter from shuffled tiles.
Word Wizard turns sight word practice into a game — Flash Cards, Listen & Pick, Spell It and Write It, from Pre-K through Grade 5.