There are two parts of your post. The first two paragraphs talk about your will to help your juniors and beginners be a better coder by taking interactive sessions in your college, to which I completely agree. But the last line speaks about “leaking” the solution, which indeed is wrong and is not fair to other participants. (And as far as I remember, they will have to face certain consequences for that.)
Learning and developing the problem solving skills should be one of the main motives and one should ofcourse help their juniors with that. But doing that while the contest is still going on, defeats the purpose of the contest. This idea of “leaking” the solution infers that learning is the secondary motive whereas improving CC ranks is the primary one. Which should not be the case.
You can take two sessions on a monthly basis on weekends once the contest is ended. The first session can be about hints for solving cakewalk to easy problems. In other session you can try to explain your juniors some more complex algorithms required to solve tougher problems.
Or you can have a CC week where on everyday after the classes you can have a discussion about one of the contest problem, different approaches to solve them. Even students should share their new approaches with others so as to broaden their thinking horizon.
But this should be done once the contest gets over.