I wonder how an editor missed that one?
I'm with you. I find errors like that all of the time in modern publications and it's jarring. Just think; there's a whole army of proofreaders and editors out there as the first wave of homeschool moms move into the next season of life. 
Those kinds of errors just jump off the page and I notice them without even trying. Drives me crazy!!!
Right there with you. Or p'raps I should say "right their with you." But one gripe per post is probably a fair limit.
When my HSed kids do one of these, I impose ___ sentences each using "to" and "too" correctly (or "there" and "their" and "they're").
And what about the change from third person singular to third person plural all in the same sentence?
Ha ha! As an English teacher, I feel your pain. It's sentences like this that make me want to become an editor and free the world of such abominable sentences. Perhaps that is what you could do after June? I think you would be good at it. You could work from home and still be a fantastic mother/wife. I could see you editing...
Despite the grammatical errors, I am interested in what the book says. Could you give us more insight? I'd love some excerpts accompanied by your thoughts... Please? =D
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