Of the other six, two each come from Wanganui Collegiate, Cullinane College and Wanganui High School, being Year 9-11 in age.
Watkin was picking Taranaki and Hawke's Bay to be the strongest sides in the tournament.
"Each team has a least one Central Districts player, so it's spread out."
Naturally, having had another strong summer with her New Zealand selections, Hinds duties and captaining Central Districts Under 21 to the national title, the team will rely on Watkin with her top order batting and spin bowling.
"I need to score some runs," she said. "But I always struggle at these tournaments. [The bowling] is so much slower, and the wickets have had a week [of games] on them, so they're slower."
Watkin will look to follow the example of her CD Under 21 team mate Monique Rees, as the Taranaki player also struggled when dropping down to a lower level to play last week in the Under 15 tournament, but adjusted and played more off the back foot to the slower deliveries to score runs around the wicket.
The first games will be at Victoria Park at 2.15pm today, then the sides will play morning and afternoon games through to the finals on Friday.