We are learning a lot from this book and sometimes we learn a lot just from trying to figure out what we are supposed to do. So, I like this book and we will continue to use it; But, sometimes what is obvious to the writer is not so obvious to a mother who has never had a logic course. It needs much more description on how the answer was derived. We have been stuck for two days on lesson 2.10 number 8. The book is excellent (although it could use a fully worked out example for each type of problem) but the teacher's manual needs more step by step instruction. ( )