The NW beat the NCU by four wickets in the first U15 girls interpro at The Rectory.
Batting first the NCU scored 76 for 6 in their 20 overs, thanks primarily to a 51-run partnership between Donacloney Mill's Joni and Annie Cunningham who made 25 and 16.
For the hosts there was a wicket apiece for Lucy Neely, Kaylee Barnard, and Cody Wallace, while St Johnston all-rounder Mansi Bhavsar picked up a brace.
(The NW and NCU Under 15 teams)
In reply, the NW lost six wickets in the chase as North Down's Gracie and Evie Keenan, Lucy Ly, Aoife Fisher, Lucy Blair and Ciara Murray got their names in the wickets column.
Among the runs for the NW were Kenya and Kia McCartney with 17 and 12, while Eglinton's all-rounder Alice McLaughlin made a vital unbeaten 15.
The U23 sides meet for the first time today (WED) at Coleraine, while the NCU U15 side play Leinster U13s next Wednesday at Rush.