Back to School: Improving Standards for Nutrition and Physical Education in Schools Act of 2007 - Directs the Secretary of Agriculture to revise the standards that set a minimal nutritional value for competitive foods and beverages (sold outside of the federally-funded school lunch and breakfast programs) so that they are consistent with those described in a report of the Institute of Medicine (Institute) of the National Academy of Sciences (NAS), dated April 25, 2007.

Requires the Secretary of Health and Human Services (Secretary) to arrange for the Institute to develop recommendations, every five years, for updating such standards so they reflect the current Dietary Guidelines for Americans and scientific knowledge. Requires the Secretary of Agriculture, after receiving the Institute's recommendations, to revise such standards.

Directs the Secretary to establish the Nutrition Standards in Schools Task Force to assist in establishing a user friendly system for identifying foods and beverages that meet nutrition standards.

Directs the Secretary of Agriculture to award grants to states, high-need local educational agencies (LEAs), and Indian tribes to provide food service and school personnel with the training needed to implement nutrition standards.

Requires federally-funded LEAs to implement policies requiring student participation in physical education programs that meet standards for physical activity issued by the Secretary, based on recommendations from the National Association for Sport and Physical Education.

Directs the Secretary to award competitive grants to states, high-need LEAs, and Indian tribes to provide teachers with the training and support needed to implement such physical education programs.

Requires the Carol M. White Physical Education program to meet the Secretary's standards for physical activity.