Do they like stars? Skeletons? Snowmen?

Suggest they find a poem; find 6 poems about a subject that interests them. Have them write the poem(s) in their own hand and see how it looks on the page.

Encourage them to try a similar first line, whether it be using a word, or using the same rhythm or syllable count. Go on from there. Extend ideas. Change them. Build on them. In other words, they can pull their idea from that poem, be inspired—then create something brand new.

Let your readers see what you want them to see: (A twisted tree, a pear tree, instead of simply a tree. A beetle, a bee, a firefly, instead of a bug.)

Poetry is in the details.