Schools and districts buy millions of dollars’ worth of professional development (PD) and training for their teachers. Collectively, Education spends about $8 Billion on total PD for teachers. In K-12, it ranges between $500 and $18,000 per teacher every year. In most schools, teachers are expected to attend the Fall intensive training, plus regular “in-line training” with online courses and workshops during the year. The 2017 Digital Curriculum Strategy Survey of 477 schools and districts shows schools offering a wide variety of training. So what’s the problem?...