Lone Peak High School in Utah is ranked #1 nationally in boys basketball by Maxpreps, despite being pretty much an all-white team of Mormons. (From the pictures, there don't appear to be any black players.) It played 10 games out of state this year and won 9, five of them over teams now ranked #1 in their own states.
This isn't a Hoosiers story about a small town school. Lone Peak is a large public high school in the suburban corridor between Salt Lake City and Provo. The community is well-to-do and thus can afford to send the team to national tournaments. It doesn't recruit much outside its school district lines, but I wouldn't be surprised if sports-minded family don't move there because of the quality of its sports programs.
The national media are amazed that Lone Peak wins (this was its 6th state title in 9 years) without black players, and that the white kids play a black Showtime style of fast-breaking and dunks. In general, I suspect that white basketball players develop better as adolescents without blacks around to intimidate them. I'm also guessing that Lone Peak's team was heavily "redshirted" by their parents because several of the players are about to leave for their overseas Mormon mission of two years -- that happens at age 19, which suggests that Lone Peak's team is older than you would expect high school players to be.
But, in general, high school sports are much less black dominated than college or professional sports. They are typically dominated by mostly white schools, either Catholic or upscale exurban like Lone Peak. In football, the usual formula for winning state championships is to have a team that's about 80% white from a school that's 90% white, but with black stars at running back, receiver, linebacker, and, say, cornerback.
For schools I'm more familiar with, Maxpreps has as #1 in California and #4 nationally the basketball team from Mater Dei, a large Catholic school in Orange County. Mater Dei is a traditional football power, with two Heisman Trophy winners among its alumni, and has the kind of weight room you'd expect to see in the SEC. Judging from pictures of Mater Dei's basketball team, it looks like it has about 3 black stars and the rest of the team is white with a few Filipinos or Mexicans.
Mater Dei just lost over the weekend to Etiwanda, previously ranked #9 nationally, a large public high school in exurban Rancho Cucamonga. Etiwanda's student body is about 19% black, and the team looks like it has four or 5 blacks on the court most of the time, with a more mixed bench.
Basketball is different from football in that you can go a long way with about 3 stars. For example, a number of years ago, a local upscale private high school (we'll call them HC) recruited the #1 eighth grade black basketball prospect in the country (he's now playing well in the NBA), found a couple of black wing men for him, and won the California state championship. This was so successful that this private school, which played my son's school in football each year, tried this same strategy with their football team.
When my son was a freshman, his school's football varsity beat HC's varsity, mostly whites and Asians with one five-foot-tall fast black freshman receiver, in a tightly fought game. Over the next two years, HC's varsity football team filled up with giant fast black players and HC would win by scores like 56-0. But then by my son's senior year, all the giant black players were suddenly gone, and HC's team was back to whites, Asians, and the tiny black receiver, now a senior, and it was once again a close game.
I've noticed that strange stuff like this happens in high school sports not uncommonly these days, although you can never find an explanation in public. How did HC suddenly acquire giant black football players and why did it suddenly get rid of them? We're not likely to ever hear the full story.