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 Effect _ Most of even beginning algebra depends on being able to do two things__one, doing multiplication quickly and accurately in your head, two, knowing how to add, subtract, multiply, and divide fractions. You might remember a concept in algebra called "factoring." Factoring means breaking up into parts that are multiplied together to give you the whole. You can factor numbers. For instance, 6 factors into 2 and 3_θx3 =6. In elementary algebra we learn to factor expressions such as x^2ƲxƲ. This particular expression is easily factorable into (xư)^2. If this doesn't make any sense to you, don't worry about it. Just trust me, if you don't know your multiplication tables, you can't factor. If you can't factor, you won't do well at all in algebra, geometry, or trigonometry.