When you join your local PTSA, you’re joining PTA—a national organization and America’s number one parent involvement resource. Your child is why you should belong. More than 30 years’ worth of research has proven that children do better when their parents are involved both at home and at school. Grades and test scores climb. Self-esteem grows. Schools improve. There’s a simple way for you to help your child succeed: Join your PTSA/PTA. You’ll belong to a community of parents committed to their children’s well-being and to improving school performance.
From the National PTA site.