[ChuckElias]

There are no "schools" that I know of to provide training on being a basketball official in the US. Most of us are trained by local associations. For additional training, many of us attend "camps" that run anywhere from one day to one week long. These camps are spread out all over the country and each has its own focus. Some are intended for beginnings refs, others for officials who want to officiate collegiate ball, and still others for officials who want to work the professional leagues.

Depending on your interest, experience level and location within the US, the camps available to you will vary greatly. If you know where you will be, and when, then maybe someone here could offer you some more specific advice.

Good luck.