There are some new materials being developed now based on what we are learning about how the brain learns. These brain_friendly materials should be an improvement over what has existed. I recently bought a book by Marcia L. Tate titled "Mathematics Worksheets Don't Grow Dendrites." I highly recommend her book. She gives a great deal of information on alternative activities that are better for your child's brain development and for learning.
The heart shape is fantastically useful for teaching all sorts of mathematical problems, including geometry. Have your child cut out a heart shape from paper and use it to help them understand symmetry. How many lines of symmetry does a Heart Have? Help kids learn about patterns by using colored hearts or a series of Valentine's Day pictures. Introduce them to simple patterns; for instance red heart, green heart, red heart. From here you can make the patterns more complex by making them longer or including a higher degree of variation. Valentine's Day is a perfect opportunity for educating your child about many math problems; from simple arithmetic and word problems to patterning and geometry. There are many ideas to choose from that you're sure to find engaging and rewarding for both you and your child. So give them a try next Valentine's Day and see if your child will be struck by Cupid's arrow and feel the love for math.