“…Although professional development is a necessary component of all educational improvement efforts (Guskey, 2000), research on its effectiveness indicates mixed results. Some studies suggest that sustained, content-focused professional development can increase teacher knowledge (Clair & Adger, 2000;Yuen et al, 2018) and change teacher practice (Desimone, Porter, Garet, Yoon, & Birman, 2002;Edinger, 2017;Garet, Porter, Desimone, Birman, & Yoon, 2001) in ways that ultimately improve student learning (Saxe, Gearhart, & Nasir, 2001). Yet others suggest that professional development does not create effective or sustainable change in teacher practice (Clair & Adger, 2000;Peters & Jolly, 2018;Petty, Heafner, Farinde, & Plaisance, 2015), or impact student achievement (Darling-Hammond & Berry, 2006).…”