I went from 5'10" to 6'2" in about the same period. Mine was between the end of 10th grade and beginning of 11th grade. Ended up being 6'5". I was short and fat In elementary and middle school and then shot up in high school. Good genes I guess. My sister and mom are both 5'10 and my dad is only about 6'1"
I believe to this day (9/7 will be 33 years ago) that growth spurt contributed to my injury as a junior in high school. My bones outgrow my muscles and my neck just wasn't strong enough whenever I've made a bad tackle.