I think the biggest effect I have seen since wrestling in the '80s is the protection of the wrestlers. I have seen a huge decrease in the number of wrestlers who get carried out of tournaments, especially in kids. Part of this may also be the quality of instruction that the kids get. They are training more seriously these days and are prepared and in better shape. The emphisis on sportsmanship is refreshing as well. We have done a better job of trying to make wrestling a positive experience for the kids. I was a ref in college (early '90s) before leaving the state for 8 years. I believe I see a definate difference these days when I ref. Also, if you look at the good high school teams they almost always have a solid kids team feeding them athletes that are already seasoned mat veterans.
As far as the highschool experience, I think wrestling can have a huge impact on the character of a student. No other sport has the same intensity and requires the same drive and desire that wrestling does. It is especially important to those who may not fit in well socially. They have the opportunity to have success on an individual level.
I think it is important to watch the health effects of losing weight to severely. I don't know if hydration testing is the answer, but I remember a number of students when I was younger that (in my opinion) were causing lasting physical problems due to extreme weight loss. The health and well being of our kids should always be a primary concern.
Hope this helps. Good luck on the paper.