A tool used in states around the country to assess teacher performance has become a lightning rod in public education circles.
The "value-added assessment" is embraced by the Obama Administration and has financial support from the Gates Foundation. The assessment compares student test performance growth from year to year.
From the Here & Now Contributors Network, Bobby Allyn of WPLN reports that proponents say it's a good tool to measure teachers.
However, some teachers and unions say the evaluations, which are often tied to pay raises and tenure, don't accurately show achievement and are filing lawsuits.
This segment aired on August 6, 2014.