Actually, there are other subjects of value that can be learned from SH3:
1) 30-60-90 triangle geometry
2) Law of sines
3) Compass headings
4) Timing of sextant readings
5) Metric system (for us imperial Americans

)
6) Knots as a speed reference
7) A little German language
8) Active/passive sonar technology
9) Radar technology
10) European geography
I'm sure there are more subjects that I can't think of at the moment.
EDIT: Oh man, how could I have forgotten SLIDE RULES!