Something like this:
Roaring Spring Engineering Computation Pad 8.5 x 11 Inches 200 Sheets Green Paper Enclosed Grid on Back of each Sheet 3-Hole Punched (95389)
https://www.amazon.com/dp/B005UOD4W2/ref=cm_sw_r_cp_api_JqCQzb6JH96JT
They're usually available (different brands) at college bookstores.
They're designed to be one sided - if you ever need to copy the graph lines aren't copied.
(FWIW, I was a physics student and did most heavy work with a Sheaffer "Student Pen" with carts, No. 2 Ticonderoga Pencils, engineering paper and those brown covered lab notebooks. Nothing super fancy, though a fair number of years ago.)
Hmm, ok. Maybe a tool like Camscanner (which I used to use to scan maps in) can do the same trick? (If you have Android look it up for taking pictures; I found it pretty handy.)
I just try not to deal with the lines at all by using engineering paper, which work by having the lines on the back so you can see through them, but the front is empty. Doesn't show up in scans or pictures at all. Nice now that I use a standard scanner for my maps to keep things relatively even and oriented properly.
Usually go with an iPad, next is pads of engineering paper (example) as a backup, and sometimes type on my laptop.
Before I got my iPad, I really liked pads like this one that had large left margins where I could put topics and stuff on the left and notes on the right. It’s nice for finding stuff when the find command isn’t a thing
I bought mine from an auction on ebay, but here it is on amazon for $12: https://www.amazon.com/Roaring-Spring-Engineering-Green-sheets/dp/B005UOD4W2/ref=sr_1_1?keywords=roaring+spring+engineering+paper&qid=1550382315&s=gateway&sr=8-1
Here it is on ebay for $10:
I guess $8 was a lower than normal price.