Let's start from preparing data table. Here is an example:
Next go to the ribbon to the Data tab. Click Data Analysis button.
If you don't have this button it means that you have to install Analysis ToolPak add-in.
New dialog box appears. Click Anova: Two-Factor With Replication option.
Select Input Range which is your data table (only numbers). In my sheet it is $A$1:$F$5. In each example (group of students) I have 3 samples. As Alpha I left default 0.05.
Anova test appears in the Output Range I defined.
Anova two factor with replication test could be useful for statistics of some sets of data. Excel does it really well.