A craft activity is a great way to convey a history lesson. A history lesson should be an opportunity to contemplate what has been long gone, as well as parts of the past that still persists in our time.
If you ever consider making a quill with your child, we suggest that you begin with the word processor in your computer. Have a close look at the many fonts available, and see if you and your child can differentiate the old looking ones from the newer ones. You will be quick to find Old English, Palatino, New Roman, Garamond, and the likes. They are the ones with stylish serifs.
Then, ask the child to gather as many different handwriting devices as possible at home. You might have ballpoint pens, felt pens, pencils, crayons, chalks. You might even have a metal quill. Ask the child to write the alphabet with each and compare the results. If you have one, use a magnifier to have a closer look. Make sure to observe the variations in the thickness of lines, as well as the presence or absence of serifs.
At this point, proceed with your quill making, to find out whether a quill will make writing in old style fonts easier. A good guide to use is one posted by the Rhode Island School of Design, aka RISD Museum on Instructible. You might also like the very detailed one by Liralen Li on this old Flick page, or one of the many videos online.
Whichever way you go about it, there are a few important things to keep in mind. First, hygiene. If you take feathers directly from a farm, make sure to clean, sanitize and dry it thoroughly before you handle them with bare hands or before cutting carefully. Second, safety. For best results, the carving requires a short, sharp blade that gives maximum control. Use more than one feather, because your first attempt might fail, or you might want to try different carvings. Once your quill is ready, get some ink and write for fun, your own secret recipe for a magic potion. Try different kinds of paper, and hang on to the one that best suits your quill.
In the end, take the time with your child to browse books or the web, and see if you can find old style fonts. One fantastic recent book about fonts is The Eternal Letter (MIT Press, 2015) edited by Paul Shaw.