Read and say time using quarter past, half past, and quarter to.
A clock face splits into four equal quarters. Quarter past the hour means the minute hand has gone a quarter of the way around, to the 3, which is 15 minutes.
Half past means the minute hand is halfway around, at the 6 (30 minutes). Quarter to the NEXT hour means only a quarter is left to go, with the minute hand at the 9 (45 minutes).
Mastery looks like: They read and say quarter-past, half-past, and quarter-to times correctly, including naming the correct hour for "quarter to."
Common stumbles: Naming the current hour instead of the next hour for "quarter to" times; confusing quarter past (15) with quarter to (45).