Estimated time to make this valentine:
10-15 minutes assembly (?)

Appropriate age group(s):
Preschool and Younger
Elementary School
Middle School
High School & Beyond

Materials:
For each card:

Construction paper (red or pink)

White doily and crayons (optional)

Stickers, to seal the card shut, or envelope to fit it when it's folded

White glue/glue stick

Pencil to write/draw with

Stickers or magazine cut-outs for various words, if you like

Penny, toothpick, 'spent' match, cancelled stamp, piece of string

Instructions:
It's a poem with word pictures glued on, or drawn; no two exactly alike, really. My son (6) brought one home from school yesterday:

"I (cent) this Valentine (2) say

I (pick) you for my own.

And tell (U) what a (match) we'll make,

if you'll (B) mine alone.

I (stamp) your name upon my (Heart),

I'll (string) along with U,

I'm giving U this card today

Because (eye) love U true."

Other comments or suggestions to consider:
I added the next-to-last line for you guys, for the "meter," but believe me, there's nothin' about my kid's Masterpiece I would change!!! It's a way cool Valentine, and a Keeper.

A paper doily could be glued to the outside, or kids could just make cool pictures with Crayons.

This poem could just be a springboard for your own creative minds. Use whatever words and pictures you like, and Draw pictures as you like.