It was just a bunch of kids roughhousing during gym class, but it was also the moment Chris Cole first saw all the potential inside Jermaine Harris.

Harris, the quiet kid from Georgia, was a gangly freshman and wearing worn dress shoes. But he could move — with the ball, without the ball, going to the rim, making space away from it — and wove in and out of his classmates during a lighthearted game of “21.” Cole, the head coach at Rock Creek Christian, excitedly recounted it to his assistants, telling them that Harris was going to be more than a player who grew faster than everyone else and was now condemned to hoarding rebounds.

Time proved Cole right.

“Everyone thinks you bring a kid up from Georgia or somewhere else and he must be really good,” Cole said. “That wasn’t the case with Jermaine. He may have been my worst recruit since I’ve been here. But now he’s passed every big man in his class in the area, and he might be the highest recruited guy around right now.”

To get there, Cole had to get Harris to trust him — or anyone — to get in shape and commit to expanding his game beyond flashes of savvy and skill. The product really broke out for Rock Creek Christian this past season, as Harris scored in double-figures in all but six of the Eagles’ games and attracted more and more high-major offers.

An offer from Maryland last Wednesday rounded out a list that includes Miami, South Carolina, Xavier, Georgetown, Georgia, Pittsburgh and West Virginia. And that’s just since the first college evaluation period in April, in which Harris was a standout for D.C. Premier at an Under Armour AAU event in New York. Before that, the 6-foot-8 forward had offers from Penn State, Rutgers, Virginia Tech, Seton Hall, Providence and Rhode Island.

Kansas came calling last Thursday with “high interest,” according to Cole, and North Carolina State has done the same. Cole said he and Harris plan to visit South Carolina, Xavier, West Virginia and Rhode Island in the next couple weeks, and then narrow Harris’ option by the end of June.

That will give Harris’ recruitment some clarity heading into three college evaluation periods in July, but another strong showing could spike more offers and interests all over again.

“This is the beginning for me, and I just need to work on some more stuff and get better,” Harris said. “It’s just the beginning.”

That stuff includes making plays off the dribble, decision-making on the move and recognizing how defenses are playing him once he starts slashing from the perimeter.

But before his development could become nuanced, Cole had to earn Harris’ trust. Harris moved to the Washington, D.C. area through a youth program run by the mother of NBA point guard Jarrett Jack. The program sought an opportunity for Harris outside of Augusta, Georgia, and Cole had played with both Jarrett (a Maryland native) and his brother. Louise Jack knew about Cole’s basketball program and asked him to take Harris, and that left the two of them at a divisive square one.

Harris was out of shape, could barely catch the ball and chose when to respond to Cole’s riding criticism. But the wheels slowly turned, and the best thing Cole could do was show Harris that listening would equate to success.

“It was always tough being away from my family,” Harris said. “But I started to get used to it.”

He did that by turning Rock Creek Christian’s gym into his new home. Harris would have to be pulled out of it at each day’s end, and the result was a growing forward with a diverse offensive skill set. He had always been the tallest player on his team, so low-post scoring was the first layer of his arsenal. He has since added a polished jump shot, a set of mid-post moves and ballhandling he is just starting to unveil.

On the other end, Harris’ quickness and length helps him stick with all five positions, a commodity college coaches are particularly drawn to. Not only can Harris thrive as the screener in pick-and-roll sets, but he can switched onto a guard while defending them and use his tools to clog driving lanes.

As summer begins and July’s recruiting weekends draw closer, Harris is looking to add even more to his game and see if the college options keep flowing in.

“His recruitment is still picking up it feels like and he is getting better every day,” Cole said. “Sky’s the limit, man. Sky is the limit.”

Recruiting notes

» St. Mary’s Ryken guard Wynston Tabbs received offers from Virginia Tech and UNLV last Wednesday, St. Mary’s Ryken Coach Pat Behan confirmed to The Post. Tabbs, who is playing for Team Melo’s 17U team in Nike’s Elite Youth Basketball League on the AAU circuit, has seen a big spike in recruitment since the first April evaluation period. Tabbs also has offers from Penn State, St. John’s, Virginia Commonwealth, Cincinnati, South Florida and George Mason, among other schools.

» Paul VI point guard Jeremy Roach was selected to USA Basketball’s U16 team Monday. Roach, a Class of 2020 guard with offers from Miami and Virginia, plays for Team Takeover’s 16U team in Nike’s EYBL on the AAU circuit.

» Paul VI shooting guard Anthony Harris, Roach’s backcourt mate with the Panthers, received an offer from Wake Forest last Wednesday, he announced on Twitter. Harris previously had offers from Virginia Tech, West Virginia, Old Dominion and George Mason.

» St. Mary’s Ryken wing Mekhi Long picked up an offer from Old Dominion on Friday, Behan told The Post. Long, who plays for Team St8tement on the circuit, previously had offers from Virginia Tech, Kansas State, Hampton, James Madison and Rhode Island.

» Maret guard Raphe Ayres has interested from Missouri, Cornell, Columbia, Holy Cross, Division III Wesleyan, and a few other D-III schools, he told The Post after a standout performance in the DeMatha Summer League on Saturday. The 6-foot-5 guard has a smooth jump shot and can also get to the rim and score in traffic.

» Springbrook junior guard Matthew Balanc has scholarship offers from St. Francis (Pa.), Norfolk State, Bryant and James Madison, and Springbrook Coach Darnell Myers expects that to pick up as Balanc plays for Mid-Atlantic Select this summer. Springbrook has two other players with Division I prospects: 6-foot-6 junior small forward Cameron Rucker has received attention from Ivy League schools. Myers has also been contacted by Kansas State, South Carolina and Rhode Island about 6-foot-6 junior guard Anthony Thomas.

» Manassas Park guard Myles Scott is receiving interest from George Mason, James Madison, Radford, Marymount and Virginia-Wesleyan, Manassas Park Coach Gary Chicko told The Post. Scott plays AAU basketball for Gainesville Elite’s 16U team and, according to Chicko, has grown three inches since the end of his sophomore season and is now 6-foot-4 heading into his junior year.

Catch up on basketball recruiting in the area …