A prospective randomized study comparing a forearm strap brace versus a wrist splint for the treatment of lateral epicondylitis, Garg et al; Journal of Shoulder & Elobow Surgery-05 April 2010.
You get the idea here- taking the stress off the extensor mechanism by way of a wrist immobilizer. They compared it to a traditional tennis elbow brace. The researchers found it did work better.
We really don't see this in the high school population, right? But you probably have a load of coaches, teacher, and maintenance guys coming to you with it. Traditionally treatment has focused on the elbow itself with cortisone injections and wrist extension exercises. But close to 100% of the time, anecdotally at least, I find the cause to be the loss of wrist extension. Of course it manifests itself in the 40's- but I believe it begins in school age.
How may of you out there have kids who can't do pushups because it hurts their wrists? They are in their teens and they already have range of motion loss. Athletes coming to you ad nauseum asking you to tape their wrists. I believe prevention should begin at the elementary school level. Forget that cup stacking nonsense. Crawling is a great upper extremity/core strength exercise, great for wrist mobility, and the variations are endless. I continue to use it in rehab.
Of course the brace will alleviate the pain. But it will contribute to the dysfunction that caused it in the first place. I personally prefer the unloading technique I described in my "less is more" post from about a year and a half ago.