Have a look here:
Valentine Bulletin Boards:
Class in a Box
Cut out a large heart out of paper. Decorate the heart to resemble a valentine box of candy. Have each child create a small picture of themselves. Glue each of your children's pictures in the heart (lined up like the candy) and write their name below their picture. You can title this board "One Sweet Box," "Class in a Box," "My Sweeties," "Our Assorted Sweeties," etc.
Give your children heart shaped sponges to paint with. Let them all create on one big piece of paper (one that will fit on the board) Next, ask the children who they love and write this randomly on the bulletin board
Simple, yet functional, Valentine Holders inspired by Ms Ross (pictured)
Students get two pieces of 12x18" red construction paper and a half heart pattern. They fold the red paper in half and trace the half heart with the straight line on the fold. They cut out the hearts and set them aside. You can do a lesson on symmetry when making the hearts.
Next, the students get a 12x18" piece of brown construction paper and trace a bear pattern.( Find a coloring page online) They use pink constuction paper to make a heart nose and the inside of the ears. They draw a face on their bear and glue it on top of one heart. Staple the other heart on top, leaving an opening to put the Valentines in. I write their name in large letters on the front of the heart so it is easy to deliver Valentines. The students LOVE this bulletin board.