Back to School By-the-Numbers We do the math on the cost of going back to school.

From kindergartners to grad students, roughly 76 million Americans are heading back to the classroom this month--but not before they hit the mall. According to the National Retail Federation, parents shell out a whopping $54.1 billion on back-to-school gear, making it a retail season second only to Christmas. The economic downturn has taken a bite out of that apple, but deep discounts and tax holidays may give this season a boost. We'll do the math:

1%-How much retail sales are expected to grow during the 2009 back-to-school season

$3.7 billion-How much parents will spend on new school shoes

$594.24- The average amount spent on back-to-school stuff for each child

3,800,000,000- The number of wooden pencils sold per year

$11.60 per hour- How much the lunch lady takes home (plus Sloppy Joes)

25%- Percentage of college students majoring in business, despite it all

$50,758- The average teacher's salary in the U.S.

15- The number of states offering back-to-school sales tax holidays