On the main PGSS website click more in the menu then choose NextCloud at the bottom or select it from the side of the main Library page.
This will let you access your Samba "H:/" drive from home. Login as you would at school.
Once logged you'll see 3 folders. Choose Home to access your saved work.
Find the work you want and click on it to download. This will give you a copy to work on. If you want to save changes you have to save them to your computer first.
Once you have saved them onto your computer go to NextCloud and click the + symbol and choose to Upload file.
Find your file and upload it. This is important, because just opening a file from NextCloud and making changes will not automatically cause the original to be updated. You have to upload it again.