I like Branagh's (1993) pretty well- it's one of the best-known, and Branagh and Thompson are well-matched as Benedick and Beatrice (they were married at the time). I usually don't like his directing that much, but it's good for the most part. There's gratuitous slow-mo at some moments, which for me is just awkward and a little funny- awkward-funny-it's-going-on-too-long-please-stop-now not haha-funny. Robert Sean Leonard is a good Claudio, managing to still be kinda likeable at the end, considering how he treated Hero. (Okay, it's the puppy dog eyes, I admit it!) The Hero is completely forgettable, I don't even remember who plays her. Some people find fault with Keanu as Don John, and while he does underact a bit (ahem), I've seen worse Don Johns due to overacting so it's a nice change imo. I think Michael Keaton disappoints as Dogberry, but YMMV. Anyway, despite some problems, that's probably the one I'd show. High school age kids will probably respond well to it, they'll know most of the actors, and it doesn't look super dated in the visual and directorial style, like some of the older films. Well as it's a club, maybe that's less of a consideration than an average HS class, but still.

The other major option is the 1973 Sam Waterston/Kathleen Widdoes version. It's the filmed adaptation of the Joe Papp production, and it's been given a setting update to the turn of the 20th century, with Beatrice as a suffragette type. I haven't seen it in years, but it's pretty good. A little slow, if memory serves.

I've only seen clips of the 1984 Cherie Lunghi/Robert Lindsey one, but it seemed ok. Same for the 1967 Maggie Smith/Robert Stephens one- Frank Finlay is a much livelier Dogberry. And wee baby Derek Jacobi is Don John haha!