To be perfectly honest, I don’t really the photos of of kids winning scholarships as a target for perverts. From what I have read and seen, perverts and their suppliers are looking for more revealing photos, and unfortunately, there are probably thousands of such photos readily available on social media. If your kid was in a cheerleading team, a swimming competition, gymnastics, etc, there is a reason to be worried about their photo being used, even if the photos are only shown on the school website. If a kid was posting photos of themself in swimwear or other revealing clothing on social media, it could be an issue. If the school was posting such photos, same thing. But kids receiving scholarships are generally not targets for perverts or their suppliers.
Bottom line, I don’t think that sickos who are looking to create porn for perverts are looking for photos of older teens in school clothes or slightly more formal clothes awkwardly holding a plaque saying that they got $20,000 from the Coca-Cola Foundation. On the other hand, it is a pretty good thing if a Google search for a kid has their scholarship win as the top result, since only the more prestigious prizes have the winners posing for photos.
All that being said, your kid doesn’t have to pose for any photo, even if they win an award. Moreover, if your family or your kid has other reasons to avoid exposure, than they should avoid any such photos or announcements that include their name.