His brother, five-star point guard Lonzo Ball, a member of the 2016 recruiting class, verbally committed more than a year ago.
The younger Ball, who is 6-feet-4, was rated a three-star recruit by Rivals.com. He is the first member of UCLA's 2017 recruiting class.
Both Ball brothers play for Chino Hills. A third brother, LaMelo, will join them there next season.
Last year, Chino Hills Coach Steve Baik told the Los Angeles Times the youngest Ball could be the best.
"Everybody in his family says he's going to be better than Lonzo and LiAngelo," Baik said.