My nephew graduated from Michigan last year. He was a decent high school player in NY, not nearly good enough to play college at any level. He and a few of his similarly-ability friends went over and got themselves involved in practicing against the Michigan women's team, and held their own against them just fine.
As far as the womens Olympic team playing against a good HS boy's team, just consider a team like Paul VI last year. In addition to the guys who came to Duke, those being 6'10" Pat Ngongba and 6'6" Darren Harris, the team also featured 6'10" Garrett Sundra, who is going to Notre Dame, and 6'7" Isiah Abraham, headed for UConn. And those were just the seniors. It's not dissing the women to point out the obvious: they would have no chance against the size, length, skills, and athleticism of a good high school boys team.