Maryland and many other states are facing teacher shortages, and yet the teaching profession loses 1 out of 5 teachers by their fifth year in the classroom. Educational researcher Linda Darling Hammond of the Learning Policy Institute says a range of factors, like planning time and access to materials, shape teachers’ decisions.And we hear from two Baltimore principals - Principal Patricia Burrell of North Bend Elementary/Middle School and Principal Marc Martin of Commodore John Rodgers Elementary/Middle School - about how they are supporting their teachers and fostering collaboration at their schools.