Final answer:
During puberty, boys generally reach half of their adult height by their 13th to 17th birthday.
Step-by-step explanation:
During puberty, boys generally reach half of their adult height by their 13th to 17th birthday. This growth spurt usually starts at around 11 years and the peak height velocity occurs at about 13.5 years, with an average growth rate of 10.3 cm (4 in.) per year. Growth in height in boys ceases by about age 18.