Picking groups

How do teachers pick groups and groupings these days? In an age of data, we know that most classrooms will have kids with plus or minus two years of ability. While some are de-emphasising ‘traditional’ school-learning approaches, we know from decades of research that reading, vocabulary and comprehension are critical to student engagement and achievement.

I am wondering, in an age of online metrics, what tools are teachers using to pre-test and/or post-test students in order to evaluate what tools and technologies are being used — and the language we use with those technologies to deliver learning?