That’s not on a main road. Zoom out a bit, the main roads are the ones leading to other villages, named after those villages (or in the case of Ulm a city in that direction).
Just like US schools, many have their own driveway that goes off the main road
Those are residential roads. This a view of the Niederstotzingen school from the road it’s on, the gymnasium is on the other side. Look up and down the road, there’s residential buildings there. Looking at the signage (or rather lack thereof), it’s two-way. No lane markings though small roads just don’t have them, you slow down and make sure to not shear off your side mirrors with the side mirrors of oncoming traffic. The little shack with a sign with an H is a bus stop. Only seems to be served by one bus line (at least I can’t find more), here’s the schelude. It connects to two train stations (including thie Niederstotzingen one) roughly every 30 minutes. Frankly speaking you can walk from there you’ll be faster than waiting for the next bus.
Niederstotzingen is classed as a city btw, almost 5k inhabitants. It’s not really a size thing in Germany though and nowadays the title doesn’t have any legal meaning, city rights were granted by Kaiser Sigismund in 1430, meaning it served as the local trade hub or such. Congratulations, thanks to wikipedia I know now more about a tiny city I don’t care about in a state I don’t care for :)