Dear Julia,
Thanks for your input. It isn't always possible to put the answer right under the problem in order to fit it all on one page. Plus if the answer involves multiple steps the side is used so you can see the work.

As far as the rest, relax, he is way further along than most children his age if he is thinking mathematically, that is the goal. Remember in most other countries math is seen as hard work, but something everyone can do. They let their children struggle. That is part of the process necessary for growth.
Nancy