As promised, here is the complete list of the poetry collections I featured in April with an extra one added in for good measure. I split the list into single-author collections and edited compilations. For each category I ordered them roughly according to age-appropriateness--with the books for younger children near the start of each list and those for older children/teens near the end of each list. Doing so is not a precise science, but i hope it aids you in finding books for a particular age group, such that you can do a closer evaluation for your particular context.
Alligator Pie, poems by Dennis Lee; pictures by Frank Newfeld. Key Porter Books, 1974.
The Llama Who Had No Pajama: 100 Favorite Poems by Mary Ann Hoberman; illustrated by Betty Fraser. Harcourt, 1998, published in paperback in 2006.
Raining Cats and Dogs, written by Jane Yolen; illustrated by Jane Street. Harcourt, 1993.
Beneath a Blue Umbrella, rhymes by Jack Prelutsky; pictures by Garth Williams. Greenwillow, 1990.
If I Had a Million Onions by Sheree Fitch; illustrated by Yayo. Tradewind, 2005.
A Book of Nonsense by Edward Lear. originally published in 1846.
When We Were Very Young, by A. A. Milne, (illustrations by Ernest Shepard). I have a reprint of the first Canadian edition, McClelland and Stewart, 1925.
Now We Are Six, by A. A. Milne with decorations by Ernest H. Shepard. I have the first Canadian edition, McClelland and Stewart, 1927.
Something I Remember: Selected Poems for Young Children by Eleanor Farjeon. Edited by Anne Harvey. Blackie, 1987.
See Saw Saskatchewan: More Playful Poems from Coast to Coast, written by Robert Heidbreder; illustrated by Scot Ritchie. Kids Can Press, 2003.
Twimericks: The Book of Tongue-Twisting Limericks by Lou Brooks. Workman Publishing, 2009.
Where the Sidewalk Ends, poems and drawings by Shel Silverstein. Evil Eye Music, 1974.
The Sweet and Sour Animal Book, alphabet animal poems by Langston Hughes; illustrated by the students of the Harlem School of the Arts. Oxford UP: 1994.
There's an Awful Lot of Weirdos in Our Neighborhood & Other Wickedly Funny Verse, by Colin McNaughton. Simon & Schuster Books for Young Readers, 1987.
Making Friends With Frankenstein: A Book of Monstrous Poems and Pictures (Candlewick, 1994)
Bing Bang Boing, poems and drawings by Douglas Florian. Harcourt, 1994.
Talking Turkeys by Benjamin Zephaniah. Puffin Books, 1994.
Carver: a life in poems by Marilyn Nelson. Front Street: 2001.
Preposterous: Poems of Youth, selected by Paul Janeczko. Orchard Books, 1991.
This Delicious Day: 65 Poems, selected by Paul Janeczko. Orchard Books, 1987.
19 Varieties of Gazelle: Poems of the Middle East by Naomi Shihab Nye. Greenwillow, 2002.
Here's a Little Poem: A Very First Book of Poetry, selected by Jane Yolen and Andrew Fusek Peters; illustrated by Polly Dunbar. Candlewick, 2007.
Lavender's Blue, compiled by Kathleen Lines; illustrated by Harold Jones. Oxford UP, 1954.
The Bill Martin Jr. Big Book of Poetry, edited by Bill Martin Jr. with Michael Sampson. Foreword by Eric Carle; Afterword by Steven Kellogg. Illustrated by Ashley Bryan, Lois Ehlert, Steven Kellogg, Chris Raschka, Dan Yaccarino, Nancy Tafuri, and Derek Anderson. Simon and Schuster Books for Young Readers, 2008.
Canadian Poems for Canadian Kids, edited by Jen Hamilton; Illustrated by Merrill Fearon. With a foreword by P.K. Page. Subway Books, 2005.
The Wind Has Wings: Poems From Canada, compiled by Mary Alice Downie and Barbara Robertson; Illustrated by Elizabeth Cleaver, Oxford UP, 1968.
The New Wind Has Wings: Poems from Canada, compiled by Mary Alice Downie and Barbara Robertson; Illustrated by Elizabeth Cleaver, Oxford UP, 1984.
Monster Poems, edited by Daisy Wallace; illustrated by Kay Chorao. Holiday House: 1976.
Sing a Song of Popcorn: Every Child's Book of Poems, selected by Beatrice Schenk de Regniers, Eva Moore, Mary Michaels White and Jan Carr. Illustrated by nine Caldecott Medal artisits: Marcia Brown, Leo and Diane Dillon, Richard Egielski, Trina Schart Hyman, Arnold Lobel, Maurice Sendak, Marc Simont and Margot Zemach. Scholastic, 1988.
No Hickory, No Dickory, No Dock: Caribbean Nursery Rhymes, written and remembered by John Agard and Grace Nichols; illustrated by Cynthia Jabar. Candlewick: 1995.
Under the Moon and Over the Sea: A Collection of Caribbean Poems, edited by John Agard and Grace Nichols; various illustrators. Candlewick: 2002.
A Child's Treasury of Animal Verse, compiled by Mark Daniel. Dial Books for Young Readers, 1989.
Poetry By Heart: A Child's Book of Poems to Remember, compiled by Liz Attenborough. Chicken House: 2001.
The 20th Century Children's Poetry Treasury, selected by Jack Prelutsky; illustrated by Meilo So. Alfred A. Knopf, 1999.
The Random House Book of Poetry for Children, selected by Jack Prelutsky; illustrated by Arnold Lobel, 1983.
The Kingfisher Book of Children's Poetry, selected by Michael Rosen, 1985.
The Oxford Book of Poetry for Children, edited by Edward Blishen; illustrated by Brian Wildsmith, Oxford UP, 1963 (reissued in paperback format as late as 1996).
The Oxford Book of Story Poems, edited by Michael Harrison and Christopher Stuart-Clark. Oxford University Press, 1990, republished in paperback, 2006.