Premiership glory will be up for grabs when 18 clubs contest 23 junior grand finals as part of a bumper schedule at Viking Park this weekend.

The ACT Junior Rugby Union will host a two-day jam-packed grand final schedule, with 18 of the 22 registered clubs having a chance to secure a title.

It will double as the first year the competition will have grand finals for the under-15s and under-17s girls grand finals, with Jindabyne/south coast to clash against Wests on Saturday and then Royals to play against Daramalan on Sunday.

Marist College and St Edmund's will play the division-one grand final as a curtain-raiser to the National Rugby Championship season-opener between the Canberra Vikings and Queensland Country.

The schools will clash again in the marquee division, the under-18s, at 3pm on Sunday in a massive rivalry battle. Marist finished was undefeated and finished at the top of the table, but are chasing the school's first under-18s division one title since 2006.

St Edmund's is aiming to win its fifth under-18s grand final in a row. Games will start at 8.40am on Saturday and finish with the under-18s clash at 3pm on Sunday.

ACTJRU GRAND FINALS

Saturday: Under-9s division one - Queanbeyan v Grammar (Sky) at 8.40am; under-9s division two - Grammar (Navy) v Wests at 8.40am; under-12s division 2 - Royals v St Edmund's at 9am; under-10s division 1 - Marist v Wests at 9.30am; under-10s division 2 - Broulee v Grammar at 10am; under-12s division 1 - St Edmund's v Vikings at 10.20am; under-11s division 3 - Bateman's Bay v Gungahlin at 10.50am; under-17s girls - Jindabyne/Far south coast v Wests at 11.20am; under-13s division 2 - Batemans Bay v Uni/Gungahlin/Yass at 11.40am; under-15s division 1 - St Edmund's College v Daramalan at 12.20pm; under-16s division 2 - Young v Daramalan at 12.40pm; under-16s division 1 - Marist v St Edmund's at 1.30pm.

Sunday: Under-12s division three - Uni-Norths/Wests v Grammar at 9am; under-11s division 1 - Gungahlin v Marist at 9.30am; under-14s division 2 - Trinity v Marist at 10am; under-13s division 1 - Marist v Daramalan at 10.25am; under-15s division 2 - Trinity v St Edmund's at 11am; under-14s division 1 - Daramalan v St Edmund's at 11.30am; under-11s division 2 - Cooma v Grammar at 12.10pm; under-15s girls - Royals v Daramalan at 12.35pm; under-18s division 3 - Wests v Cooma at 1pm; under-18s division 2 - Marist v St Edmund's at 1.30pm; under-18s division 1 - Marist v St Edmund's at 3pm.