I recently switched my dd6 over to Math U See Alpha and so far we are REALLY liking it.
I'm thinking ahead a little bit as to whether or not it would be worthwhile to start my ds in Primer for his K year, or just skip it until he is ready to start into Alpha. It looks like there is a lot of overlap between the two - Primer just taking some of the introductory concepts for Alpha a lot more slowly. Part of me wonders if we could just skip Primer, and spend time playing around with the blocks, decimal street, etc during his K year without actually buying the Primer books. On the other hand, I do like the idea of having something all laid out for me to do with him, as I don't really have a lot of time to piece things like that together for myself. He also really likes to be involved in our school time, and I think he would like having his own math book.
So, thoughts? Is it worth the money to buy the Primer books for a K-er who likes to be included in school time?