About as dangerous as basically every other school bus.
School buses tend not to be particularly impressive, unless you're someone who finds weird smells especially enthralling. But this one is a whole other level of vehicle. The bus was built from the ground up and is powered by a General Electric J79 jet engine, the same one used in the F-104 Starfighter and the F-4 Phantom II. This allows the bus to reach speeds of 367 mph, which is why the ground up build was necessary, as it's unlikely a regular bus would survive those kinds of speeds.
The bus is named "School Time," and the owner says he built it to encourage kids to take up an automotive hobby and to stay off drugs.