I found a template of the Budget Challenge Cash Flow Spreadsheet. It has the following Column Names:
A - Date
B - Deposits
C - Bank fees
D - Apartment
E - Renters Insurance
F - Car loan
G - Car Insurance
H - School loan
I - Cable
J - Energy Bill
K - Cell phone
L - Credit Card
M - Withdrawal
N - Deposits
O - Checking Account Balance
P - Comments
Interest Earned should be entered in Column B - Deposits because the interest earned will automatically credited by the bank system into the bank account of the account holder. It will then be added in the Deposits total found in Column N. You can then note that the amount deposited is the interest earned in the Comments section in Column P.