both in high school, grade 10-11. There’s also another one I know who in grade 9, was going 11.5, high 11.4s at his best, then went to 10.9 in grade 10, and then 10.4 last year. Came 2nd at world youths. Not sure how much he lifts, but based on size, i can say close to none! lol.
The one who swears by the weights, i know everyone can talk about physical maturity, but going by appearance alone, he didnt gain much height if any during the year he gained a lot of speed. He also didn’t “look” much more mature physically, other than that he added a lot of mass.