Debi,
One source for patient education literature in Korean is Washington State's
Healthy Mothers Healthy Babies, Korean version.  Its available through
ICEA's Bookcenter, 800 624-4934.  I understand it contains material on
nutrition and birthing in Korean.
Perhaps the couple's interpreter can translate some of your own written
materials for them, or translate labels for any charts or visual teaching
aides you use.

One of my several CBE teaching sites is in Queens, NY, which qualifies
beautifully as a multi-cultural melting pot.  At that site, in any one class
I may have students from a variety of countries, some more fluent than
others.  I call them my U.N. classes, as in United Nations.   I wish you the
best with the wonderful challenge and learning experience that this
opportunity brings to you, as well as your students.
Joyce Blangiardo RN, LCCE, FACCE, IBCLC
LamazeLady+AEA-msn.com