Team competition

We are teaching students English. Don't teach students something neither fish nor fowl, such as PK. Formal English is nothing more than a competition, so you can use contest or competition, or contest is the most appropriate.

Come on! Fight for victory, we are the best team!

Go! Be a winner!

We are the best team!

Running for victory is too China-like, and the most appropriate slogan in English is be a winner, which means that students should succeed.