These have great reviews on amazon.

bumping 'cause I'd like to know too - and for what age did you use/try them?

My friend had a math one. I have not heard back on whether she liked it or not.

I recently bought the "Painless Writing" book at a discount shop. I have begun reading it, and have picked up some good tips already.

It's pretty easy to read and understand, though I felt at times like the author was occasionally a little wordy. Not a big deal to me, though, because the information is placed in a very easy to read format. This particular book has segments that gives a tip with a simple explanation, followed by actual writing exercises. The answers to the problems are located in the back of the book.

HTH!