Revisions/Updates to the TM

[Mathmommy]

Can someone tell me what changes are made in the revisions/updates to the TM? I have a 7 year gap between my oldest children and my youngest children. There could potentially be two revisions in the TM before my younger children get to the curriculum. Some of the books we've loved, and some, not so much. So, I'm secretly wishing that some of these books get switched for something else

Are the updates minor such as type-o's that are fixed, updates to page numbers when new editions come out, new books when some go out of print?

Or are there major updates such as a new books/curriculum that is better, additions or deletions of whole sections?

Thanks!

[StephanieU]

So far, Carrie had only made major changes when absolutely necessary, due to books going out of print. But she has also been busy writing a new guide each year, so she hasn't had time for anything else. I do not know if she plans on making any "optional" major changes after she finishes the last high school guide next year. I know she spends a lot of time researching books, but there are always new books being written as well that might fit/work better.