Hi,
Thank you for contacting Microsoft Community.
I appreciate your time and effort.
I understand that you unable to get add-on products.
I will certainly help you with this.
As you mention that you are using Windows 8.1 pro for education. You may need to contact the school IT admin, so that they can help you on this issue.
You can also post your query on Microsoft TechNet forum for this issue. There you can get more effective and appropriate suggestions by experts familiar with this topic. Your understanding is appreciated.
Here is the link for Microsoft TechNet forum:
Please let us know the results. Feel free to write us back for any further assistance with Windows, we’ll be glad to assist you.