Detroit Country Day head coach Kurt Keener said the decision came down to his official visit, as he just didn't feel like it was the best place for him.
"When he took his official visit out there he didn't feel like it was a good fit for him," Keener said. "He thought that maybe he had committed a little too early and rather than making a mistake and going with something that his heart wasn't in, he decided to open it back up."
After opening up his recruitment, Riley and Keener have been busy answering phone calls. Among the schools that have shown interest are California, LSU, Temple, South Carolina, Iowa State, Minnesota and Kansas.
"Right now he's just kind of seeing who is interested in him," Keener said. "The schools that have expressed interest and he shares interest in they've exchanged phone numbers and he's just going from there."
"Since we announced that he has opened his recruiting back up we've gotten quite a few calls and he's been just kind of filtering through those and has indicated to probably four or five that he has an interest in their school. So they are going to begin the recruiting process with him."
The Jayhawks are recruiting Detroit Country Day junior Ray McCallum, who transferred in from Indiana in the summer, and they made an initial call expressing interest in Riley if another scholarship opens up.
"Kansas is recruiting my point guard and they may have interest in him if their big man decides to go out early," Keener said.
Riley, a four-star prospect ranked in Scout.com's top 75, struggles with consistency, but when he brings it, he's among the best big men in the country and has the skill set to score inside.
"He's doing well in practice and we had our first preseason scrimmage on Saturday and he seems to be stronger and more confident with what he's doing offensively," Keener said. "I've been pleased with his progress, but it's still so early."
Detroit Country Day gets their season under way on December 12th against Ann Arbor (Mich.) Pioneer.