Adams got to Westpac Stadium around 7am and stayed for an hour, running basketball drills and training with the students.
"He made time for all of the kids and took time with everybody," Cross said.
"He's exactly the same as when he left, which is awesome to see because he's obviously been in the spotlight over there and living the high life a bit."
He said that when Adams left the training he said he was "off to his aunty's house for a feed."
NZBA coach Kenny McFadden said training with the academy was part of Adams getting "back in to routine"
"He's definitely happy to be home."
He is thought to be splitting his time at home between Wellington and Rotorua.
His arrival back in New Zealand after a disappointing loss for the Thunder to the San Antonio Spurs in the Western Conference finals.
Adams revealed this week that he would not be playing for the Tall Blacks at this year's Basketball World Cup, focusing the NBA Summer League with the Thunder.
Joe Webb has played basketball with Adams since they were 13 and said it was great to be back in Wellington with him.
"It's good to see him... he's one of my good mates. He hasn't changed a bit, he's just the same good dude."
He said it was part of Adams' character to want to spend his time at the NZBA with the young players.
"It's just like him to give back to up-and-coming basketball players."
He said the young players "went a bit harder" when Adams showed up.
Mr Webb, 20, has also been playing basketball in the US, and is hoping to be playing in the College League in August.
