Epoptes is an open source computer lab management and monitoring tool. It allows for screen broadcasting and monitoring, remote command execution, message sending, imposing restrictions like screen locking or sound muting the clients and much more!
It can be installed in Ubuntu, Debian and openSUSE based labs that may contain any combination of the following: LTSP servers, thin and fat clients, non LTSP servers, standalone workstations, NX or XDMCP clients et

You can find also some specialized software such as :
School Calendar: School Calendar is a universal calendar for teachers and pupils from high-schools and colleges, letting them track lessons and tasks to do, organize the studies more effectively than before.
Educator: Educator is software for classroom management. It enables teachers to present their work to all students in classroom without using projector. With Educator, teacher can take full control over student