Hugging Heart: To make this adorable hugging heart you may need to do some of the initial prep work, but your toddler can work on many steps with you including tracing the heart shape and folding the paper arms, gluing on the various pieces and decorating the heart face. Like most projects for this age level, you may need to help with the cutting, but it's okay to let your child try safety scissors and to start teaching a 2-year-old to cut with scissors herself. This is a great valentine to mail to grandparents or loved ones who won't see your child for the season, since it let's them still enjoy a "hug" from their favorite tot.
Make a 3D Heart: I don't know what it is about 3D artwork from kids that I find so cute, but I just can't get enough of it. They are super simple to do with toddlers. Using sturdy paper (or even recycled paper grocery bags), cut out two identical large heart shapes; I recommend making them at least 18 inches high. Let your little one paint one side of each heart any way he wants. You might limit his color choices, though, to pink, red, and white to keep with a St. Valentine's Day theme. Let the two painted hearts dry. Lay one heart on top of the other (painted sides facing out) and staple the top and sides, leaving a space a little larger than your fist at the bottom. The staples shouldn't be more than 2 inches apart, so you may need to use a lot of staples for your child's piece. Through the opening stuff crumpled up paper (old newspapers and magazines from the recycle bin work perfect) until the heart puffs out nicely. Poke a hole through the top and hang it from the ceiling if possible so you can fully enjoy the 3D effect.
Coloring Pages: Your toddler doesn't need to be a great artist to create a masterpiece. Print out free coloring pages for St. Valentine's Day and have her decorate them with any of a number of artistic tools -- crayons, markers, paints, stickers, or even dot-making bingo daubers. You can cut out these pictures and paste them on to card stock to create unique St. Valentine's Day cards.
Finger Paint Kisses and Hugs: Making X's and O's (also known as kisses and hugs) with her fingers is a great way for a toddler to practice manual dexterity while you teach her about circles and lines. You can whip up some homemade finger paints for the project. Then create a protected space where your child can freely paint without worrying about the mess.
Personalized T-Shirt: Even if you don't think your toddler is ready to create a special painting for the family room, you can still help her design a one-of-a-kind master piece by using hand prints to create a colorful t-shirt or special apron loved ones will cherish.