"We were up a bit late last night."
The players from Tupou College and Tonga High School have joined more than 10,000 athletes from 303 schools competing in 22 sports in the 14th Anchor AIMS Games.
The team arrived in New Zealand on September 5 and spent time training in Auckland where they stayed with Kiwi relatives.
"We could not afford to stay together," Mrs Tupouniua said.
"A lot of the team have grannies or uncles and aunties in Auckland for them to stay with."
The team caught a bus from Auckland to Katikati on September 8 in time for the tournament.
Mrs Tupouniua said they were lucky to find accommodation with a family in the Tongan community at Katikati.
"They have been looking after us. That has saved us some money."
The team competed in their first games on Monday, and Mrs Tupouniua said three of the six girls won all their games in the individual heats.
"One of the girls beat the top three seed which was a highlight for us."
Players through to the first-division rounds would play for medals on Tuesday evening and the second and third divisions would play-off for a placement.
Mrs Tupouniua said although any win is a major achievement for the players, it was more about identifying how well their top athletes went against players outside of Tonga.
Playing badminton in New Zealand was "totally different" from back home, Mrs Tupouniua said.
"We have plastic shuttlecocks to train with, and this is the first time we have had proper badminton shoes on a proper court.
"Normally we would be playing under the coconut trees somewhere," she laughed.
"We do not have the facilities that they do here."
The Tongan team travels back to Auckland on Saturday, and will spend a week with family before returning home.