Every teacher has had the experience of writing the same thing on fifteen or twenty students’ notebooks because the students were allowed to leave the classroom before the teacher discovered that the students hasfailedtounderstand some crucial point.

…teachers work in groups to devise questions to find out whether their teaching has been successful. …questions that give us this window into students’ thinking are hardto generate, and teacher collaboration will help to build a stock of good questions.

Questions
Mainly managerial
A third required only recall
Only 8% required students to analyse, make inferences or to generalise
Less than 10% of questions caused any new learning
Addressing this seems like an obvious way to improve student learning.