There are two ways to upload several files at once.

1) Use 'Folder' module

You can check how to upload the folder at 'Instructor's manual: Upload class material > Folder' document.

You can check differences between file and folder module  at 'FAQ: File/Folder' document.

2) Upload file by 'Drag&Drop' in classroom page.

You can convert to editing mode by clicking the 'Edit' button which is at the right side of page.

By clicking the several files  you can  drag them to weekly box. (Drag&Drop)

Uploaded as 'file' module.

(Note) Uploaded as a name of file.

(Note) Change the detailed settings like name, mark style, etc at the page of file settings.