Asking pupils to put their hands up is not an effective way of judging whether children have absorbed what they are being taught.
This is the opinion of Dylan William, former deputy director of the London Institute of Education, who pointed out that the same pupils always have their hands up, meaning teachers have no idea if the rest of the class understand.
In an interview with the Guardian he claimed teachers should get lollipop sticks with their pupils' names on them and select them at random to answer questions.
Alternatively, Mr William said students could be provided with mini whiteboards to write their answers on and hold them up for the teacher to see.
He also spoke out against handing out too many grades and not enough constructive criticism.
"I've nothing against grades at the end of the school year. But telling students, after every piece of work, that they're at levels 5, 6 or whatever is bizarre, perverse. The national curriculum levels were meant to be descriptions of the totality of achievement over an entire key stage, not judgments on individual pieces of work," Mr William added.