But Tauranga fought back with some tenacious defence, marshalled by openside flanker Flynn Kelly, and rocked Rotorua with two quick tries to fullback Cole Forbes and first-five Jake Malbon.
Forbes kicked a penalty to close the gap to just six points and with the final play of the match Tauranga attacked inside Rotorua's 22.
But a desperate tackle turned the ball over and Rotorua were able to clear before international referee Nick Briant blew full time.
Rotorua Boys' coach Ngarimu Simpkins expected nothing less than the full on confrontation his side received.
"With the coaches and setup they have at Tauranga Boys' we thought we were going to be in for a tough game and we certainly got that," he said.
"Tauranga took their chances but we scored some beautiful tries. I think they were the best we have scored this year and it is really pleasing to see some desire coming from the boys."
Tauranga Boys' coach Dan Goodwin felt it was a lost opportunity to knock over the national champions.
"I am disappointed for the boys. They showed good intent and they could have won. We came back but our set piece let us down and pretty much that was the difference," Goodwin said.
"We might have fallen asleep a little bit after halftime thinking the wind was going to win it for us. But I am still happy with the boys and seeing the improvement. It is about making sure we put the complete package together.
"That is our goal to keep on improving. We want that belief back in the school that we are a good rugby school."
As national First XV Rugby champions Rotorua Boys' played in the Sanix World Youth Rugby Tournament in Japan in April.
Simpkins says it has been a settling down period for his team since then.
"It is really good for us to get our feet back on the ground and get into some hard work. We know nothing is guaranteed and everyone is up to beat us so we have to work hard during the week and put it in a solid performance on the Saturday," he said.
"Our No 8 Viliami Tosi played particularly well and also our captain Jaya More. He led from the front taking the ball into contact and I also thought Reuben Te Kani Taylor our fullback covered the ball well today.
"Special mention of Tama Te Aute, younger brother of Isaac, who came up from the under-15s and played a good game today."
Rotorua Boys' High School 24 (Jaya More, Viliami Tosi, Tama Te Aute, Hayze Perham tries; Kaleb Trask 2 cons) Tauranga Boys' College 18 (Leroy Carter, Cole Forbes, Jake Malbon tries; Forbes pen). HT: 5-5
