WIS narrowly lost 39-37.
Captain Kopere Tanoa was then named in the tournament team for his efforts over the previous five days, with WIS ultimately winning eight of 11 games against some strong sides from traditional youth basketball hotbeds.
"It doesn't happen often," said coach Terry Tanoa.
"I'm very proud of our boys, they regularly only pick the tournament team from top four players.
"The tournament itself is just massive, they're pretty sharp here.
"Every other team in the competition, they know who we are now. It's put Wanganui on the map for basketball."
WIS debuted at the games this year by sending their basketball team.
They were among 228 schools nationwide taking part in the variety of codes in Tauranga, which was a sharp jump from last year's 10th anniversary games which boasted 193 schools and 6500 athletes.