Hi there, Susan1216. 

Allow me to share some information about creating purchase orders with multiple classes in QuickBooks Desktop (QBDT). 

You can customize Purchase Order Template to add a class to each item in the grid. Here's how:

1. Open the Purchase order and click Formatting beside Main. 

2. Click on Custom Purchase Order Template and click Additional Customization at the bottom. 

3. Select Columns and put a checkmark on the class and click OK.

I've added screenshots for your visual reference. 

To learn more about the class tracking feature, you can read this article: Set up and use class tracking in QuickBooks Desktop.

Keep your post coming if you need more help with creating purchase orders. I'm always around to help. Have a great day!