I am absolutely blown away by this curriculum. It is worth every penny and then some. For the first time EVER we didnt have tears during math, it was the complete opposite. My 11 year old with ADHD & cusp of Autism soaked up this way of learning.. using just about all your senses. At the end of each lesson she teaches me what she learned. That has never happened before. She completely understands why, how, and everything in between. Although Gamma has been our first Math-U-See curriculum i highly recommend all of them due to this way of teaching/learning. You go at the pace of your child and my child fell behind (more like left behind) when she was in public school, so Gamma was the perfect starting point for us. It works for younger and older kids, even teens. It is not grade based but mastery based which i love. I wish the public school systems taught this way of learning. I dont think I could of gone another year of our homeschool math if it wasnt for Math-U-See. It makes me emotional to see my child thrive like this. We have been using their Spell-U-See spelling/writing curriculum for almost 2 years now. I wish I knew of Math-U-See sooner. This is amazing and simple concepts for kids of all ages and abilities to use.