No. It’s not free.
Actually, llama3 is free, but best I can tell, it takes a $300,000 computer to run it.
If you have some budget, you could set it such that you pay that much monthly to whatever service you want to pay for and when it’s used up for the month, it’s used up for the month. You’d try to set up limits so that it wouldn’t happen the first week (or day). It would be complicated to set it up such that teachers who wanted to use it as part of class could count on it.