The poet WH Auden coined or adopted the phrase 'memorable speech' to describe poetry (rather than define it). This is a rich vein to explore: 'memorable' implies both 'easy to remember' and 'worth remembering'.
There are many ways that we make poetry memorable in the sense of 'easy to remember' eg through rhythm, repetition, patterns of imagery, contrasts, ironies, figurative language that surprises us, humour, rhyme and so on.
Likewise, we have many ways to make it worth remembering: choosing subjects that matter to us, whether personal, cultural, political. Or perhaps to do with the world we go through: poetry can stop and look closely at something that might otherwise pass us by.
In a school context, poetry offers some educational aspects that people are concerned about. Because poetry is memorable, we offer young people 'chunks' of language that becomes portable. They and we want to remember it. One of the ways in which we acquire the shape, sound and grammar of language is to remember chunks of it. Again, and related to this is the way poetry can often act as a bridge between the spoken and the written language. As Auden observed, it is a specialised form of speech. A lot of it sounds like the spoken word, and most of it can easily be spoken. And yet it isn't speech, as speech in conversation is full of hesitation, incomplete fragments, interruptions, and a method that often needs more context and human gesture to make sense.
Another way to look at poetry is to see it as a specialised form of cohesion in language. Poetry sets up ways of making language cohesive using sound, repetition, exploration of lexical fields, contrasts, patterns of imagery and figurative language.
This then becomes a platform for helping young people explore symbolic language. There are many ways poems use symbols or a whole poem can be taken to be symbolic or representative of something bigger than itself. A haiku about a leaf falling may be representative of something much more than a leaf falling.
We've reached a point in education, where reading and writing poetry is something that has been quietly and silently shoved in a cupboard. Poetry in education isn't of itself or inevitably 'good'. It can be taught in a dull, tedious way especially if it's dominated by exams and the formulas needed for the exams. Poetry thrives when young people feel free to explore it and write it how they want to. This calls for poetry to be in poetry-friendly places, where poems are up on walls, where the kinds of questions we ask about poems are to do with how and what a poem might mean to you, how it reminds you of things about yourself, or other things you've read or heard, what questions you would like to ask of people in a poem or of the poet, and what the 'secret strings' in the poem that are the links between the sounds, images and lexical fields.
It's easy to forget that poems are ways that writers start conversations. We hope that a poem will fire off conversations that readers and listeners will have in their heads and with other readers and listeners. An exam-driven curriculum is much more likely to regard poems as boxes full of a finite number of facts and the job for a student is get the right facts and a sufficient number of right facts out of the poem. It's as if the system asks of students to think of a poem as an egg-box, and the student's job is get all six eggs out. To carry on the analogy, yes, it's possible to take eggs out of a box, but eggs only really start to matter when we think of things to do with them - fry, boil, poach, use in making cakes and so on. In other words, poems only matter when we can use and adapt what we find in them. That means listening to how we use our experience of life, experience of 'texts' (in the widest sense ie including songs, films, TV programmes) to lift meaning from a poem. 'What does this poem (or line, or phrase or word) remind me of?' 'What thoughts are triggered by the poem, line, phrase or word? Why? What's the link between what's written in the poem and what I've started to think about?'
This last is a matter of how we make links between two things - something in a poem, and something in our heads. If we can articulate what that link is, or what is in common between the two things, it may well be the first step towards abstract thoughts and ideas. The common point might be, let's say, 'disappointment' or 'regret'. One thing educators can do, is helpe students articulate and discuss such beginnings of abstract concepts that link poem (or part of poem) to student's experience.
Books I have written which are entirely or partly about poetry: 'What is Poetry?' ( )