Sure, I can help you set up a random name generator in Excel for your classroom use. Here are the steps:

1. First, create a list of all your students' names in a column in Excel. You can add or remove names from this list as needed.
   
2. Next, in a blank cell, enter the following formula:
   Code:

   =INDEX(A:A,RANDBETWEEN(1,COUNTA(A:A)))

3. This formula uses the
   Code:

   INDEX

   and
   Code:

   RANDBETWEEN

   functions to randomly select a name from your list of students. The
   Code:

   COUNTA

   function counts the number of names in your list, and the
   Code:

   RANDBETWEEN

   function generates a random number between 1 and the total number of names in your list. The
   Code:

   INDEX

   function then returns the name corresponding to that random number.
   
4. Once you've entered the formula, press Enter to see the randomly selected name. You can copy and paste this formula into as many cells as you need to generate multiple random names.
   
5. To make it easier to use, you can assign this formula to a button or shortcut key. To do this, go to the Developer tab in Excel (if you don't see this tab, you may need to enable it in Excel's options). Click on the "Insert" dropdown and select "Button" under the "Form Controls" section. Draw the button on your worksheet and then right-click on it and select "Assign Macro". In the macro dialog box, enter a name for your macro (e.g. "RandomNameGenerator") and then click "New". In the Visual Basic Editor, enter the formula from step 2 into the macro code and save it. Now, whenever you click the button, the macro will generate a random name.
   

That's it! You now have a random name generator in Excel that you can use for calling on students in your classroom. Let me know if you have any questions or need further assistance.