Typical teacher... no sense of humour...
Anyway, there's the Uetliberg, which can be reached by a train from platform 1 of Zurich HB. There's the Pfannenstiel, which can be reached via platforms 23 and 24, catching a bus at Meilen. Further afield, there is Rigi which can be reached by getting the train to Arth-Goldau and catching the cogwheel railway to the top.
The chances of seeing the sun at any of them, however, are entirely dependent upon the weather.
Do they have maps at that school at which you teach, I wonder?