Treecology: 30 Activities and Observations for Exploring the World of Trees and Forests is an excellent new nature activity book for kids of a fairly wide range of ages.
Like a tree, the pattern of the book is pretty straightforward but fractal like; you start off simple but end up pretty much anywhere in the world of ecology. The book begins with the basic definition of a tree, simple tree anatomy, some phylogeny, some tree physiology and biology, but then branches off (pun intended) into things that are related to trees, like things that live on them, eat parts of them, etc. Seeds and seed dispersal come in around this point as well, as one might expect. The role of trees, or tree related images or tree names, etc. in human culture is also explored.
As indicated by the subtitle, these lessons are organized into thirty things you can do. Some of these things simply involve looking (dividing your local landscape's larger plants into "tree" and "not a tree,", etc.) while some involve more intense observation (like telling different trees apart) or interaction (including, of course, waxing leaves and similar activities).
The book includes some great tips on observing (or attracting) forest insects. I think Huxley's Buggy Camp could have used some of this info this week to help them find tree-related buggy creatures in the nearby woods.
This book can probably work in any North American region, as it is not too specific at the species level, and pretty generic at the genus level. As it were. There is more than enough activity in this book, in terms of both amount and diversity, to keep a family with any number of kids busy on several weekends. The activities are also spread out across seasons fairly well.
Monica Russo has written and illustrated several nature books for children, and authored "Nature Notes," a column in the Sun Chronicle. Kevin Byron is a nature photographer who's work is widely recognized.
The book, published by Chicago Review Press, will be out on September 1st, but I think you can actually order it now.