In providing professional development, teacher leaders focus on particular subject matter content or pedagogical approaches intended to build the instructional skills and abilities of classroom teachers. (mspkmd.net)
The information also allows teachers to differentiate among academic levels, grouping kids together according to how far along they are with particular subject matter. (hechingerreport.org)
As for particular subject matter, I don't like narratives, basically. (widewalls.ch)