From The Practice of Poetry. Write a poem in which some major change (in style or content) occurs across a stanza break. The poem should not explicate or comment on the change; it should rather absorb or reflect it. This may seem mumbo jumbo-y, but once you get going, it will make sense.
From Thirteen Ways of Looking for a Poem by Wendy Bishop: You might try a praise song of a natural environment that praises a single element, like Gerard Manley Hopkins does when he praises spotted and dappled and freckled things. You might praise elements of flying things or aquatic things. You might praise the foods (and in doing so the culture) of your youth to explore what you felt then and what you know now.
From The Writer’s Idea Book by Jack Heffron: Write about a family ritual. How did it start? Why has it continued? Do your family members have nicknames for each other? How did they start? Why do they stick? What do the nicknames suggest about the roles people play in your family?