They succeeded 2019 champions, and local rivals, St Andrew’s College, to secure the crown for the sixth season since 2010.
CBHS, who previously claimed the title in 2017, finished the six-team one-day competition unbeaten at Lincoln on Monday.
Wellington College were runners-up; New Plymouth BHS, Hamilton BHS, Westlake BHS and Otago BHS were the other provincial representatives.
Coach Jack Harris praised his players' composure as they chased down challenging targets against Westlake and Hamilton.
“When you’re chasing a big score like that it can be overwhelming, especially at schoolboy level, but the boys definitely held their nerve and played sensible cricket,” said Harris, the nephew of former Black Caps allrounder Chris Harris.
First-year opening batsman Robbie Foulkes, 15, earned particular praise for his unbeaten 127 as CBHS beat Northern Districts’ representative by five wickets after being set 269 for victory.
Foulkes made 252 runs at 126.0 while fast bowler Gus Sidey was adjudged tournament MVP by snaring seven wickets at 12.0.
“Gus has been doing a lot of work with Dayle Hadlee in the Canterbury A set-up. He’s turned into a real weapon,” Harris said.
The Cup triumph capped a dominant season for CBHS, who also hold the secondary schools’ equivalent of the Ranfurly Shield - the Heathcote Williams Challenge Shield.
They also won the Christchurch Metro one-day, two-day and T20 competitions.
He initially shared the coaching position with Blair Hartland earlier this year, before taking charge when the season resumed in September because the former Black Caps opener had other commitments.
“It was a bit of a step up and being a young coach,” he said, admitting there were some reservations.
Harris, who played for the CBHS 1st XI before finishing school in 2017, feared it would be tough laying down the law because he was in the players’ age group.
“I thought it was going to be a hard having that balance between being a good mate and making sure they listen and respect what you say when you do say something serious,” he said.
“I’ve been amazed how they responded to that.”