Kerri wrote:
I won a trip to the Dominican Republic recently and I need to know if
my boyfriend can just use his birth certificate and driver's license
to fly out of Canada and return. He's an American Citizen.

It took me about 40 seconds to find this on the Canada consular
information sheet on travel.state.gov. Read the last sentence carefully,
emphasis added.

"When entering from the United States, U.S. citizens must show either a
U.S. passport or proof of U.S. citizenship such as a birth certificate,
naturalization certificate, or expired U.S. passport and photo ID. U.S.
citizens entering Canada from a third country *must have a valid passport.*"