I must stress here the point that I appreciate clarity, order, meaning, structure, rationality: they are necessary to whatever provisional stability we have, and they can be the agents of gradual and successful change.
Once every five hundred years or so, a summary statement about poetry comes along that we can't imagine ourselves living without.
Even if you walk exactly the same route each time - as with a sonnet - the events along the route cannot be imagined to be the same from day to day, as the poet's health, sight, his anticipations, moods, fears, thoughts cannot be the same.
Poetry leads us to the unstructured sources of our beings, to the unknown, and returns us to our rational, structured selves refreshed.
Besides the actual reading in class of many poems, I would suggest you do two things: first, while teaching everything you can and keeping free of it, teach that poetry is a mode of discourse that differs from logical exposition.
Everything is discursive opinion instead of direct experience.