I know for southwest airlines you can bring on a carry on and a personal item. Is a book bag considered a personal item? Thx!
A book is a personal item but a bag that is 10 x 16 x 24 is considered a carry on item. Other personal items allowed by the airline include: purses, cameras, food containers, briefcases or a laptop.
http://www.southwest.com/html/customer-service/baggage/carryon-bags-pol.html All i can find