In a video released by the school, Boynton held the letter as multiple players read portions of it before Reeves was called forward to learn he'd been placed on full scholarship.
Boynton said Reeves' work ethic helped him earn the honor.
Reeves' father averaged 21.5 points and 9.5 rebounds as he led Oklahoma State to the 1995 Final Four. He then shattered a backboard during an open practice at the Final Four and the video of the dunk was the first item published on ESPN.com when the site launched in 1995.
"Coach [Randall] Dickey gave me a perfect pass off the backboard, so I decided to try to dunk it backwards and when I did, it just happened to shatter," Bryant Reeves said then.
After Friday's surprise, Reeves' son said he was humbled by the scholarship announcement.
"Can't begin to express how grateful I am for this!" Trey Reeves tweeted. "Extremely blessed to be part of such an extraordinary program! Love you guys!!!"