How can I copy a file from a modern machine to a “vintage” Macintosh?

My son is working on a school project, the subject is the history of Mac computers.

He’s writing a paper but has to create a visual display too.

I suggested displaying his paper live in MacWrite on an old Mac.

We can get an old Mac easily, but how can we copy a file to it? The best I can come up with is retype it.

We have Windows machines and a Mac Mini, but no other Macs.

Is there a cable that can make a PC or a USB drive look like an external disk drive? Or a USB floppy drive that can write an old Mac floppy disk format?

Update: Based on information on this website I think I can use an old SCSI CD-ROM drive with a Mac Plus.

Solution 1:

A USB to DB9 or DB25 adapter, a Null Modem cable, and Kermit on both ends.

I'd just re-type it, but I got Cs in school.

Solution 2:

The most common hardware interface shared by both new and old macs is Ethernet (you may need an additional Ethernet card on some old mac). From this, any IP-based protocol should work, including Appleshare IP. For converting the paper to Macwrite, I suggest plain text.

Solution 3:

A USB floppy drive would probably be the simplest method. Shove a blank disk in the Plus and let it format it there, then see if it mounts on a newer Mac.