Dunstan scored six tries and lively halfback Matt Enright kicked four conversions in the southern division game.
Enright delivered quick ball, enabling the young Dunstan backs to play with confidence. Two who stood out were first five-eighth Logan Cornish and centre Canaan Napier.
Dunstan began strongly, scoring four tries and leading 26-0 at the break.
Verdon College had a more effective defensive screen in the second spell and slowed the game down. Dunstan's loose forwards Daniel Riley, Simon Lloyd and Daniel McBreen were quick around the paddock and linked efficiently with the backline. They each scored a try.
Dunstan had pace on the wings, where Jared Napier and Lachie Edwards both scored tries.
A strong St Kevin's pack set the foundation for a 23-5 win over newcomer Mt Aspiring College, in the northern division game in Oamaru.
The key players in the pack were loose forwards Callum Knowler and Jacob Coughlan, who dominated the breakdown and linked efficiently with the backs. Powerful prop Sione Palaa was strong with the pick and go and used his strength to bustle over for a try.
The best St Kevin's back was fullback Hamish Slater, who was dangerous on the counter-attack and when entering the line.
Midfield back Josh Ngao scored his second try of the competition. The other try was scored by halfback Jackson Reid.
In other games in the southern division, Gore beat Menzies College 13-6 and Southland Boys' beat James Hargest College 43-10.
