We homeschool and stuck with a mastery based learning for my boys but my daughter needed something different. We are so glad we changed to Horizons for her. She loves the constant review of previous concepts. I love how she is learning different topics as well. She totally learns better with the spiral approach presented within these books!
I've used Horizons Math for the past 5 years now and won't use anything else for elementary grades. The colorful pages are so engaging, the lessons are steadily paced with continuous review, and my kids just plain love them. The teacher's books are great too for giving me ideas of how to teach something if I get stuck with them and can't quite get them to understand me on my own.
This is our first year using Horizons Math and both my daughter and I love it. It seems advanced for third grade, which is not a bad thing. I love how each lesson has a little bit of everything learned in previous lessons. The review is great for my daughter and she loves how colorful the pages are. She isn't bored or overwhelmed by the work because there isn't a million questions that all look the same. It is the first math curriculum she has had that works so well for her. I know this will be a successful year in math for her.
With their spiral curriculum, Horizons Mathematics sets a very strong foundation for students! My kids seldom need review of a particular concept but when they do worksheets are available. Such a curriculum should be used in all math programs!!