The Weekday function returns a number between 1 and 7, that represents the day of the week.

Syntax
Weekday(date[,firstdayofweek])

Parameter 	Description
date 	Required. The date expression to evaluate
firstdayofweek 	Optional. Specifies the first day of the week.


Can take the following values:

    0 = vbUseSystemDayOfWeek - Use National Language Support (NLS) API setting
    1 = vbSunday - Sunday (default)
    2 = vbMonday - Monday
    3 = vbTuesday - Tuesday
    4 = vbWednesday - Wednesday
    5 = vbThursday - Thursday
    6 = vbFriday - Friday
    7 = vbSaturday - Saturday

Example
<%
response.write(Weekday("2010-02-16",0) & "<br />")
response.write(Weekday("2010-02-16",1) & "<br />")
response.write(Weekday("2010-02-16",2) & "<br />")
response.write(Weekday("2010-02-16",3) & "<br />")
response.write(Weekday("2010-02-16",4) & "<br />")
response.write(Weekday("2010-02-16",5) & "<br />")
response.write(Weekday("2010-02-16",6) & "<br />")
%>
The output of the code above will be:
3
3
2
1
7
6
5