LMom,
I have heard a lot of parents of non-mathy kids (I don't ask for IQ scores- ha ha) say that Singapore's Primary Math doesn't have enough review. They are usually not using anything but the textbook/workbook combo.
This is what we do (two gifted kids -- one is "mathy") --
textbook, workbook, intensive practice
I find the Challenging Word Problems aren't more challenging than the word problems in the Intensive Practice books. The CWP books are too much review. I do have them, but I only pick and choose among the problems and only when added review is necessary for that kid on that particular topic.
I don't use the instructor's/home educator's guides because, quite frankly, the method is so obvious to me from the textbook. I do have most of the home ed guides and I have looked through them. I even tried to use them a few times. Mostly, though, I had already gleaned what I needed from the text and saw it simply put into words in the guides.
We sometimes only use the textbook. Sometimes a kid just seems to already know the topic and even the Sinagpore method for that topic (probably because the kids have used SM all the way through and they just picked up on the pattern). Sometimes I even just "throw" the book at the kid and let them do an exercise on their own (usually when they ask for that).
Sometimes we add manipulatives or a little extra review to a topic... drill or whatever... depending on what that kid needs for that topic.
Obviously I'm not going to criticize the way anyone uses Singapore's Primary Math curriculum, as we use it all those ways, too. Of course, if someone complains about SM not working and then admits that they don't try to use all of what is available to them for that particular topic (guides and additional Singapore books include more practice, ideas for games and using base-10 blocks, drill etc.), well then I have no sympathy. Ha.
I have a friend whose PG kid does Singapore curriculum on his own (textbook only) and sure seems to get the method from my point of view. Gifted kids don't always fit the rule, so flexibility is the key.
