I'm in the US, in a small suburb of a city. We live about 3 miles from the school and they are on the bus for about 20-25 minutes. Most of the route is only one lane each way so there really isn't anywhere for a bus to pull over without blocking the drivers coming up behind it. Traffic is very light in the general area of our neighborhood so that wouldn't necessarily be an issue and, if a car did come along, the bus driver could most likely immediately wave the car to go around without any problem.
My son reads very well - we didn't realize how
well until he was recently grounded off all electronics for 3 weeks and blasted through the last 4 Harry Potter books
. That said, I doubt he could navigate a map entirely successfully since he doesn't drive or know the names of all the streets along the route. I think it would be easiest for him to pay attention to where the driver is and guide her from memory.
Having the route programmed into a navigation system would be ideal but I'm not sure how practical it would be since each driver seems to have a specific bus (as opposed to the bus staying with the route while the driver changes). When the kids have substitute drivers they can tell as soon as the bus turns down our road because it's different than their usual bus. There'd need to be a program that allowed the drivers to download the route into their gps as needed, probably wirelessly or from a computer at home. Plus there'd be the cost of supplying each driver with a device.
I think WillyNilly's suggestion that the driver have written instructions to refer to between stops is the best idea. Personally, that's how I drive when I'm heading somewhere unfamiliar - memorize the first few steps and then consult the directions at stoplights and memorize the next few. Yes, it might cause a delay, but they were 20 minutes late as it was. The lateness didn't bother me, I'll cut a lot of slack for a new driver. I'd rather they drive the route carefully than have to backtrack for missed stops, wrong turns, etc.