Smithsonian Discover: Flight accessories-watches The flex collar fits behind

The flex collar fits behind your neck and can be removed if desired

One of the most intriguing new characters in Star Wars Episode VII

" "Machines in the Sky

This beautifully illustrated guide to the history and science of flight answers questions that kids ask (and parents may not be able to answer)

"Smithsonian Discover: Flight" brings the awe-inspiring experience of visiting the Smithsonian's National Air and Space Museum alive in the pages of a book

Smithsonian Discover: Flight accessories-watches The flex collar fits behind"Smithsonian Discover: Flight" brings the awe inspiring experience of visiting the Smithsonian's National Air and Space Museum alive in the pages of a book. This beautifully illustrated guide to the history and science of flight answers questions that kids ask (and parents may not be able to answer), such as "What makes a plane stay in the air?" "What's a sonic boom?" and "How do astronauts go to the bathroom in space?" Arranged into three sections,