Hi, My second grader and I just did a quick and easy homemade Valentine's Day card project this weekend. We took red construction paper, made 20 hearts (one for each classmate), and then my daughter wrote each student's name on each card and decorated the cards with stickers and markers. We uploaded a photo of the cards in the comments section of this Education.com activity: http://www.education.com/activity/article/make-valentine-cards/

There are other homemade card ideas here:
http://www.education.com/seasonal/valentines/homemade-cards/

Here's more information about Valentine's Day etiquette, and why it's important to have a card for every child in your son's class:
http://www.education.com/magazine/article/Valentines_Day_Etiquette/

You can share your feelings about this experience in this related JustAsk Q&A: http://www.education.com/question/feel-kid-class-celebrating-valentines/

Thanks for asking!