I wanted to read this book ever since seeing the infomercial of Scott doing his thing on tv. I couldn't afford or justify the expense to buy the big commerical package so this book had to do. The methods are easy to follow and Mr. Flansburg does a good job expressing his mind set in how he mentally did the problems. The basic addition and multiplications methods are good but the examples were insufficient when dealing with mixed numbers of different lengths. There were also exceptions to many of the rules that weren't expressed. Finally, the last part of the book with special rules were so numerious it would take a year to effectively learn and apply them all from memory. This leads me to believe that Mr. Flansburg didn't tell everything he knows, like the quick way to determine change -- by changing say ten bucks to 9.99 and subtracting that from the amount owed; then add one cent to get the correct change. It's easier to subtract 9 since its the highest value you can have in each column. This was presented by him on a night time radio show he was a guest on. I do give him prasie for getting people young and old to stop depending on calculators and learn mental speed math.