My daughter was 4 at the time and I read through the first chapter. It showed a method of teaching with fingers as manipulatives. I still wasn't thinking of it as a math curriculum but some interesting math tricks. So I did lesson one with my daughter (age 4) when waiting in line at the grocery store and during errands and thought not much more of it.. till I got upset one day. I had started with a 10 dollar bill and lost some money somewhere. I verbally went through my day... saying how I had spent 5 dollars at one place and 1 here, three there... My 4yo was listening and piped up "Mommy, that means you should have 2 dollars left! Can I have one?" It was then I realized these 'math tricks' had taught my daughter more in a few minutes waiting in line than I ever imagined they could. We love the curriculum and use it as our main Math program. It just makes sense, rather than being a struggle to learn math.