count if with sum product

Hello,

This one has me stumped. I am trying to count the rows in sheet one that have the value in column A in all columns in sheet 1. For example, on the Class on Jan. 2013 sheet (I did this one manually), there are 150 rows which have the value D6 in all columns in sheet 1. I have tried this formula but it does not seem to be working. Any suggestions?

=COUNTIF(Sheet1!I2:W36278,SUMPRODUCT((Sheet1!I2:W36278='Class of Jan. 2013'!A3)))

Thanks!

Laura