If you can get an auto egg turner, the weekends will not be a problem. Best day to start classroom eggs is on a Wed.
The 2 ways I've found to hatch eggs in the classroom are:
1. Borrow a teaching kit (incubator / egg turner & lesson plans) from a local source. For us, our county Agricultural office has an education dept that loans out incubation kits. Some state (or county) 4H branches also have similar units. If you're near a university, they may also have an incubator you may borrow. If you're very lucky, someone in your school district may already have an incubator.
2. Creative grant writing. There's all kinds of funds available to teachers if you can submit a request to the right people. Egg incubation can be used for health class (embryo development), agriculture grant (poultry), general science (data recording skills, scientific method), etc. I once got a clean water grant to purchase a mini koi pond for my classroom so we could do an annual study. Basically, you have to ask what kinds of grant proposals they are looking for & gear your request towards that. (ie- the DNR wanted to fund something to promote the clean water act, so my idea of testing water quality in the classroom pond was enough to grab attention.) My school district once gave me a grant to pay for 1/2 of my expenses for a graduate class in Belize & Guatemala. (Mayan temples & Tropical rain forest studies) Our school district wanted to add more about the Ancient North American Cultures to the 6th grade curriculum. I offered to climb a couple Mayan temples, visit a few archaeological sites, & learn a little about the culture while I went there to study animal adaptations for my science curriculum.
Side note: I miss those days of my youth. I was in the process of submitting my paperwork to our district for an earth sci grant to study volcanoes (Project LAVA = Learning About Volcanic Activity), when I discovered I was pregnant. Hiking around volcanoes while pregnant & clumsy no longer sounded appealing. My new adventures as a mom had begun!