Need Help By Tuesday -VARIABLE INTEREST RATE HELP HELP HELP

Hi,

I know how to use basic functions in Excel, but need a solution to what I consider a tricky problem.

Our ministry is running an investment contest for our 4rth graders and here's the scenario:

You invest a fixed dollar amount of say 5000.00 dollars on January 1st 2007. Then, every day you recieve a different percentage in dividends. Say 1.2 percent on the first day, 1.41 percent the next day, 0.9 percent the third day etc.

I need a way to enter each days interest rate and understand this will be a daily entry, BUT we need ONE FIELD which is our initial investment field to add each days interest, to that single field for all the days listed. I'm not sure if that makes sense.

It is kind of like a compound interest calculation for ONE FIELD (The Initial Principal), but with daily changing interest rates.

I was told to create an open ended ARRAY, but need this figured out by Wednesday to show the kiddos how all this stuff works.

Please Help.
Eddie