Yes, why not? The teacher is getting paid for 10 months worth of work but is getting paid over 12 month period for the convenience of the Yeshiva. This is NOT done in any other industry. You are saying straight out that they are getting paid for WORK that they did over a 10 month period however the employer is spreading out their payment over 12 months.
What about schools that are late in paying their teachers. Does that mean if a teacher gets fired but is NOT paid up to date, they can’t collect for the weeks that they receive a check in the future? Unemployment does NOT go according to WHEN a person gets paid, it goes by when a person WORKS and gets paid for that work. So just because it is more convenient for the school to distribute the payment to their employees over a 12 month period, why shouldn’t the teacher start collecting from the very first day after the 10 months are up? That is the very first day that s/he is unemployed.