A lot of poetry books are handled as large-format picture books, with only a dozen or so poems, lavishly illustrated. Those are often wonderful. That approach works even with a single poem, like "Owl Moon" or "Hist Whist."
Then there are the massive collections by some of the most popular poets for children. Those sell very well because they're funny at first reading, but the poetry is often not very rewarding after that. They get old really fast, because those poems depend too much on silly situations, on nonsense verse, and relentless rhyming. Just my opinion, but I think children shouldn't consume too many sweets, fries, soft drinks, or trivial poems.
When I was in grade school, I liked poetry about as much as you did. I found it especially interesting when the ideas were big ones, even if the words were small. Robert Frost's poems were like that. I still have to pause and think quietly when he says "I shan't be gone long. You come, too."
Since I grew up in cold country, I knew exactly what Christina Rosetti means when she says "Earth as hard as iron, water like a stone." When Robert Louis Stevenson asks
Late in the night, when the fires are out,
I search myself for a clue. But I loved the nonsense verse of Walt Kelly and Lewis Carroll, too. The words were so cool. "Beware the Jubjub Bird, and the frumious Bandersnatch!"
This isn't old fashioned. Poetry is poetry, and what makes it good today is just the same as ever: memorable language, wrapped around a memorable idea.