Their second match is this morning against Wellington B.
"It doesn't get any easier but there's a chance to play at a higher level, one that these boys might not get in Whanganui," said Mason.
Kickoff is 11.45am.
The team will have a rest day tomorrow and then their final match of the tournament on Thursday.
Meanwhile, former Whanganui High School player Vilimoni Koroi has been named as a winger in the 2016 New Zealand Schools team to play Fiji and Australia next week.
Koroi, now at Feilding Ag, went to the wider squad training camp under coach Jason Holland this month.
NZ Schools play Fiji on October 3 then Australia on October 8.