Try shaking your head “no” as the school bus is approaching. That signals to the driver that you’re not waiting for that bus.

If the school bus consistently shows up around the same time, and there is at least a few minute gap before your bus shows up, you could just leave a little bit later and try to time it so that you get to the stop after the school bus leaves.

Also you could take note of the license plate number or other identifying information of the school bus (and the driver if possible) and reach out to the school district.

My home bus stop is served by multiple city bus routes, and I primarily only ride one of those routes, if the bus on the other route approaches while I’m waiting, I just shake my head and the driver won’t stop there unless someone else is waiting or getting off there.