Within minutes, Volpenhein received a congratulatory text from U.S. Olympic gold medalist and future Stanford teammate Katie Ledecky.
"I heard the good news," Ledecky wrote. "Congrats Ashley and welcome to the team! Go Card!"
Volpenhein was the OHSAA Co-Swimmer of the Year last season. She is the high school state record holder in the 50- and 100-yard freestyle.
"She had a great visit (with Stanford)," Mason coach Mark Sullivan said. "High academics, as you know, and she loves the team."
Volpenhein, a USA Swimming National Junior Member, represented the country at the World Junior Championships in Singapore in 2015. She has been a part of the Manta Rays club team for 12 years.
She also considered Southern California, California-Berkeley, Michigan, Virginia and Texas among her college choices.
"The entire Mason Manta Ray Swim team family and City of Mason couldn't be prouder or happier for Ashley," Manta Rays coach Ken Heis told WCPO.com. "She was worked extremely hard for all of her accomplishments and now she gets to swim for her dream school. Stanford offers the best of both - academics and swimming. Stanford's engineering program is a perfect match and the top ranked swim team allows her to pursue her swimming goals on the absolute highest level."
The OHSAA swimming and diving season begins Nov. 28.