Or you could make a smaller one.
Equipment needed;
Fair sized sweater tub w/lid deep enough for bricks and plastic shoe boxes.
Bricks
Plastic shoe boxes w/lids
Submersible aquarium heater.
Aquarium thermometer.
Perlite, available at garden centers.
Aquarium power head or fountain pump. Optional.
Take the big sweater tub and put the bricks in the bottom. Space them close enough to support the shoe boxes. Place heater in bottom and fill with water to within 1/2" of the top of the bricks. Add the power head for water circulation.
Fill shoe box/es 3/4 full of perlite which has been mixed with water. 1 part water to 10 parts perlite. Put thermometer in perlite and put cover on box. Place box on bricks and turn on heater and pump. Set temp on heater and wait a couple hours. Check temp of shoe box and adjust as needed for your snake eggs. Have this set up and ready to go before your eggs are produced.
When eggs are laid be careful not to change orientation of eggs, you can mark the top with a #2 pencil. If eggs are stuck together don't try to separate them. Place eggs in perlite mix and bury about 3/4's deep but leave tops of eggs exposed. Put cover on shoe box and on incubator. Check daily for the first few days to be sure your temps are correct. Then weekly for moldy eggs and to be sure eggs aren't deflating. If you notice any deflating spray water on sides of shoe box not on eggs. Normally you shouldn't have to add water to perlite.
Air holes are not needed, with the regular checking of the eggs they will get adequate air exchange. I like the use of the power head or fountain pump to keep the incubator from having any hotspots. This is a simple incubator to make and more reliable than a Hovibator by a long shot. It also fits in with your class project but probably won't take more than an hour to make.
BigT
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Hope this helps.
BigT
There is a difference between ignorance and stupidity. The ignorant can be taught, stupidity is beyond our control.