Scholastic Atlas of the World
This is our go-to book for basic info on every country we study. It's very detailed and could easily be used for much older students. We use it mostly for detailed maps and to fill out our country fact sheets that I print from Enchanted Learning.
My First Picture Atlas
It looks like this particular one may be out of print, but there are two things about it that I love, and that you could find in another similar book. First, it's huge. It's about 11'x14", which makes it great for group work. The maps inside are large, bright, and cartoony, which makes it very easy to see borders, capitals, and other important landmarks. When the kids are doing their map work, this is the one I prop up for them to use as a reference because it is so bold and easy to follow. The National Geographic Picture World Atlas looks just as good and is available from Amazon and other retailers. I wouldn't use either of these beginner atlases as my only map source since they are very basic, but they are a very nice addition to use along side a more detailed book.
Usborne Stories from Around the World
Kids Multicultural Craft Book by Roberta Gould
This book contains 35 craft projects from around the world. Each entry also contains a good amount of cultural information about the author's experiences in that country (and even includes some photographs from her travels). The craft ideas are very good, have detailed instructions and are not babyish (no paper plate masks, etc.). The only downside for our class is that a good number of them require several steps or long drying/setting times between steps, but for most families this would not be a hindrance.Unicef's Children Just Like Me Meet the families of about 40 children from around the world and discover what their daily lives are like! The kids absolutely love this book, as it brings to life the similarities and differences between cultures in sweet and simple ways.
Another similar book is Children from Australia to Zimbabwe: A Photographic Journey around the World by Maya Ajmera & Anna Rhesa Versola. This book has more information about the geography and the larger culture in each of the countries, including favorite foods, sports, past times and holidays.
My group likes to cook, so we've used two different books for our recipes. First is Eat Your Way Around the World by Jamie Aramini. This one includes a full meal for each country, so we usually choose one or two pieces to make (usually dessert!). There are also great cultural references included such as how food is served and what traditional foods signify in that country. And the recipes are delicious, which doesn't hurt.
Kids Around the World Cook! is the other one I find myself grabbing. The recipes are simple and traditional, and the recipes are arranged not regionally but by course. So, all the drinks are together, all the desserts are together, etc. This makes it easy to prepare just a side dish or a beverage to sample the country's flavors without pulling out all the stops for a full meal.