My 2 cents.
I. If you want "action photos" I would recommend the smallest focal length. (the 35mm)
This is because a manual lens is harder to maintain in focus, and the shorter focal length will give you a bit more room.
II. If you want "portrait", and they can pose for you, try the widest aperture (the f1.4) But depends on the max shutter speed.
III. For some "documentary style", (the kids sitting watching some other kids, and you taking the photos a bit far away) use the longest focal length, (135mm) at the widest aperture.
IV. Always keep the Sunny 16 rule in your mind. (Or prepare a cheat sheet) https://en.wikipedia.org/wiki/Sunny_16_rule
V. If you want to freeze the action, try an ISO 400 film and adjust the exposure accordingly.
VI. Try to keep a record of the shutter speeds you use.