Could you re-wire a table lamp if you had good written instructions? IF the answer is yes, I'd get the kids involved in a project to MAKE an incubator. Hubby and I have built 2, both are forced air. One has a bimetal thermostat, and the other has a digital. You can build a GOOD forced air incubator for around $20 if you are a good scrounger. You can get a free styrofoam box from a pet shop or a pharmacy. Or you can use a cooler as your box. check out Rush Lane Poultry for his many "how to" videos regarding building an incubator. Look for the video for the digital.
Check out this thread, post # 19. https://www.backyardchickens.com/threads/which-incubator-recommendations-needed.1222951/page-2
Check out this thread, post # 19. https://www.backyardchickens.com/threads/which-incubator-recommendations-needed.1222951/page-2