To the original question, is she supplying the rods? Is it something the school needs modifying, or are you providing the material? Is the OD 3/8?
You say the thread will be 1in long on 3/8"x16TPI? What is the length of the rod? Will it fit through your spindle? Is there enough room to mount the rods in your setup? (Personally, I cannot mount long rods as my lathe is in a recess in the wall.)
Do you have a 3/8x16 die? If so, and the material is supplied by your friend, and it's 3/8OD, it should be a relatively quick job compared to manual thread cutting.
Say 10 mins setup + 10 cutting using die, filing, deburring etc = 20mins / thread = 3 threads/h.
@ 24 threads, then you could be lining yourself up for 8h work.
What is a full working day of your life worth to you? With Covid going round, you may be glad for a distraction.
Also think about wear on your tooling.
As others have mentioned, you could treat it as a business or as a donation.
If it's a donation, maybe get your friend to pay for a decent quality die and a few bits of tool steel. It'll make the job easier, and you'll have a new die from it, and they'll be getting a decent deal too.
Personally, my job is about evaluating impact and true cost to have changes implemented.
If your friend has been quoted hundreds by other companies, and it's something they have to get done, you will be doing a favour charging anything less than they have been quoted. That said, that is just using other people's pricing.
Whilst I understand the view that some schools are crap, there are also some very god schools with dedicated and caring teachers working in less than ideal conditions. It may be different in other parts of the world, but here, no-one goes into teaching to get rich!
Just my 2c.