OK, I found this information myself and will post here for anyone who might be interested. This is specific to Maryland, so you might want to research it yourself for your specific state.
Hours:
Minors 14 and 15 years of age may not be employed or permitted to:
•· work more than 4 hours on any day when school is in session
•· work more than 8 hours a day on any day when school is not in session
•· work more than 23 hours in any week when school is in session
•· work more than 40 hours in any week when school is not in session
•· work before 7:00 a.m. or after 8:00 p.m. Minors may work until 9:00 p.m. from Memorial Day to Labor Day.
•· work more than 5 consecutive hours without a non-working period of at least 30 minutes.
Hours of work for minors employed by an employer covered by the Federal Fair Labor Standards Act are more restrictive than those allowed by Maryland law. In general, it is the more protective standards which apply.
Minors 16 and 17 years of age:
•· May spend no more than 12 hours in a combination of school hours and work hours each day.
•· Must be allowed at least 8 consecutive hours of non-work, non-school time in each 24 hour period.
•· May not be permitted to work more than 5 consecutive hours without a non-working period of at least 30 minutes.
Division of Labor and Industry
1100 N. Eutaw St. - Room 606
Baltimore, MD 21201
(410) 767-2239
FAX: (410) 767-2986
E-Mail Address: dli@dllr.state.md.us
http://www.dllr.state.md.us/labor/wages/empm.shtml