Create drop down lists based on data entered in two previous cell???

So here is my problem.

I have three data sections (Day, Session, and Course)

Day - Monday through friday (drop down already created)
Session - Only session 1 or session 2 (drop down already created)
Course - Certain courses are only available during certain days and certain sessions (this is the drop down i need help with)

How do i create a drop down list that only returns the course available for the day and session listed above?

I have attached a sample workbook, the drop downs are found in the attendance tab while the courses available during each day an session are in the codes tab.

Any help would be greatly appreciated.

Thanks in advance

Los

Thanks for the link, but i am having a hard time creating the lists maybe its the way i have my data set up. In the sheet attached above i have the data broken down by day then session and then the course listed below. i don't know make excel know which courses are offered on which day and which session.

I am an excel movie so these tutorial are little bit hard to follow sometimes

Thanks for any help that can be given

Los

It should be attached in the original post....but i will reattach

Awesome thanks for the help....

Los