With data on enough teachers, researchers can estimate average improvements of teachers over time, and they can identify the effects of professional development or other programs and practices on teacher improvement. (carnegieknowledgenetwork.org)
Student achievement data show above - average improvement in schools in which transformational leadership coaches have worked. (ascd.org)
Value - added measures allow us to estimate average improvements over time and link those to the experiences of teachers (carnegieknowledgenetwork.org)