K-12 - Am I able to order Diploma Covers before I order Inserts? Yes, you may place an order for covers at any time. Related to diploma Related articles K-12- How can our former students order replacement diplomas? K-12 - Is a PO (Purchase Order) Number necessary to place a Diploma order? Diploma WebCenter Help K-12 - How can I pay my diploma invoice? K-12 - WebCenter is not allowing me to submit my diploma order, what should I do?