Number 15 — fifteen. The flat-topped 5 follows the 1, and fifteen apples fill three complete rows of five — the set’s best count-by-fives sheet. Two tracing rows, the solo row, and the word fifteen.
Fifteen is the flat-topped 5 after the 1, and it marks the halfway point of the teens. The 5’s hat, down, and around chant still works in second place. Fifteen apples fill three complete rows of five, the cleanest counting-by-fives picture in the whole set: 5, 10, 15, with no leftovers at all to confuse the count.
Extension: count by fives out loud using the rows — 5, 10, 15 — then keep going on fingers to 20 and 25. Draw fifteen more apples scattered under an apple tree in the margin, and count the full orchard: the two fifteens together make thirty.
