After I make a piece of art with chalk pastels, it gets smudged all over. I don't want to go out and get fixative, and we don't have hairspray, so I was wondering if there is any household item that works well as a fixative for chalk pastels?
Here are some additional recipes to complement fixer1234's extensive answer:
The easiest and most likely candidate for a homemade fixative is milk.
Van Gogh protected a lot of his drawings using regular milk (and water)1 - at times pouring out entire glasses over them. The reason he opted for milk was because he wanted to get rid of the sheen of charcoal and graphite.
If you happen to have any casein lying around, a casein fixative might be a good alternative.
Mix casein with (grain) alcohol and (distilled) water, in a 1:2:5 ratio.2
See here for more experiences (and likely some troubleshooting).
And in case you have any shellac at home, you can try mixing it with isopropyl alcohol in a 1:4 ratio to create a shellac fixative3, which you can apply using a spray can.
1: http://vangoghletters.org/vg/terminology.html, see under 'fixing'
It will be easier for people to offer relevant answers if we know your constraints; what you want to avoid. I would think lots of clear spray finishes could work in a pinch (hair spray, clear paint-type finishes like lacquer, etc.; and spray application would avoid smudging). If it's a question of cost, it's just another art supply to protect your effort. If it's a question of fumes, many kinds of products will be in the same boat. If it's a question of corona virus and not wanting to venture out for a non-critical item, you could avoid handling the art until you can get a proper fixative. So let us know your objective beyond just needing a fixative.
There are fixative sprays optimized for the purpose, and hair spray will also work. Once you get away from things that are designed for the purpose, there will be trade-offs and risks, and they generally won't be as good. I'll suggest a few (untested) ideas of items you might have around that might help to prevent smudging, but they are also likely to affect the appearance. You would probably want to experiment with scraps of the paper and some chalk scribbles before trying something with art you want to preserve.
If you want to use something other than an actual fixative or hair spray, you will probably come closest with very light mistings of a clear spray finish. You want to apply just enough to act as a binder without building up a shiny layer. Pretty much anything else will be much more noticeable and affect the appearance.
Anything water-based will affect the paper, but you might get away with misting a few fine coats of something like acrylic floor finish or even diluted PVA glue from a distance with a hand sprayer or paint sprayer. Let each coat dry completely before applying the next. If it's heavy enough for complete coverage that produces a shiny surface, it's too heavy.
You would want to shoot for coats that each make almost no visible difference; just a dispersion of tiny droplets, with not enough in one spot to swell the paper. If you build up too thick a layer or don't let each layer dry completely before applying the next, it may warp or curl the paper because the overcoat will shrink as it dries (less of a problem with a collection of tiny independent droplets).
Anything you apply with direct mechanical means, like a brush or roller, is likely to smudge the chalk. An approach that might work would be to pour a thin layer of non-water-based clear material that doesn't shrink as it hardens, like slow-setting epoxy. That will produce a very different finished appearance, though, than the very matte finish of chalk on paper.
For that matter, there are products like versions of Mod Podge that are designed to be "poured" from an applicator to provide a clear surface over paper. Paper thinner than cardboard usually needs to be glued to a surface to prevent it from warping.
Just thinking outside the box, an idea you could experiment with (I have no idea whether it would work), would be to iron on wax paper. The heat might transfer some of the wax into the chalk and paper and act as a binder. There could be a problem trying to remove the wax paper without having the chalk stick to it (try it hot and cold).
Another consideration is longevity. Products other than a fixative designed for the purpose may change characteristics over time. Many products, including hair spray and some finishes, may eventually yellow. Organic materials, especially without preservative, may decompose or be attacked by microorganisms, PVA glue and some other materials can become cloudy in high humidity, etc. So a lot of materials may be fine to protect the pieces for awhile, but they could ruin work you want to have an archival life.