CSET Physical Education Subtest 129 Practice Test

During puberty, girls typically begin physical development earlier than boys. On average, girls start around ages 8–13, while boys tend to begin a bit later, around 9–14. This earlier onset in girls is driven by hormonal changes, especially estrogen, which leads to earlier development of secondary sexual characteristics and growth spurts. Because of this pattern, the statement that girls develop before boys is the best description of their relative timing. There is variability and some overlap—some boys may show rapid development that seems close to or even overlaps with late girls’ development—but the overall trend favors earlier development in girls.