One of the players in the winning team was 11-year-old Camryn Tidy, who started playing the sport when she was in pre-primary.
The Salter Point resident said she enjoyed playing with friends and learning new skills.
"It felt really good to win because we are a small club and don't win many of these carnivals," Camryn said.
"This is my last season playing teeball and I plan to play softball next season as I love the game."
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READ NOWThe under-12s team was selected in late November with the players competing in three lead-up tournaments.
Assistant coach Meg Tidy said there were eight teams in the under-12s B division.
"We were hoping to win a few games, but to take out the title, we were ecstatic," she said.