April is National Poetry Month!
Poetry 4 Kids offer lessons for writing poetry. I recommend an acrostic poem if you are just starting out! It also offers a lot of other poetry resources.
Scholastic offers a lot of teacher resources for National Poetry Month.
At Poets.org, you search by poems or poets. There are even videos of various poems. Classics and more.
DLTK offers this collection of spring poems. This is a little more of a "kid" friendly selection.
Poetry for Kids offers all kinds of poetry based links including places to post poetry you've written, a link to a rhyming dictionary, and more.
Readwritethink has some cool online tools that actually help write various types of poetry.
Apples 4 the Teacher has a thematic list of poems which includes various holidays. How about memorizing a poem for Armed Forces Day or Bird Day. (You know how I feel about every day being a holiday!)