school inter-class ball-game tournament
A school event where classes compete against each other in ball sports such as basketball, volleyball, or dodgeball. Similar to クラスマッチ.
See also: クラスマッチ
At next week's ball-game tournament, our class is aiming to win in basketball.
The events for the ball-game tournament have been decided as dodgeball and volleyball.
クラスマッチ is a more general term for inter-class competitions that may include non-ball sports or cultural events, while 球技大会 specifically refers to ball-game tournaments.
Compound of 球技 (ball game) and 大会 (tournament, convention).