I like these train sketchings very much Dennis! A train seems like the perfect environment to practice drawing. You've got the people, of course, doing all sorts of activities, the different textures of the materials in the train, the reflections on the glass, the outside environment going by (which could be interesting to try to draw in motion). I usually sketch during/between class or while on the shitter
. You mostly get bricks, benches, and people reading books. In the bathroom, you get ducts and sinks and dirty cloths. Neither is very diverse when compared to a train.
Going back and forth from strict reproductions of what I see to free imagination faces and abstract geometry seems to do the trick for me. The strict reproductions are always more rewarding personally, though.
I never ask permission to draw anybody. I don't really care if this is rude, but it might be useful to have a talk about the ethics of asking people for permission to draw their likeness.
