I think they use pagers on freq 72.10000 and 462.7500
The 72 MHz freq is licensed for wireless clock synchronization in the school, and 462.75 is licensed for wireless public address/school bell control.
I would agree that it is likely that the schools are using one of the Futronics trunking systems. Here's a link to a Futronics license where Norwalk Schools transferred control of a license to Futronics back in 1998: ULS License KNJT851
I would expect that the schools received some type of compensation for the transfer of control such as discounted radios or airtime.