Brain Teaser about School Pupils with Hints and an Answer That Tasks the Mind

Today's brain teaser is about a government school inspector who was impressed by a teacher whose pupils all knew the answers to the questions asked during lessons. Here's how the code was cracked.

A government school inspector was on duty at a local primary school to conduct regular checks on teachers' performance to either praise or proffer better learning methods.

After going through all the classes, he was especially fascinated by one of the classes and the teacher. When he got into the class, he watched how the teacher-pupil relationship ensued and was impressed.

While the teacher gave out the day's lesson, the pupils paid rapt attention, and each time the teacher asked a question, every pupil would have their hand raised.

The inspector also noticed that the pupils got the answers correctly, and it was a different pupil every time a question was asked. This got him highly pleased and curious.

He also observed that none of the kids were prompted or coaxed to raise their hands when it came to answering questions, and they were all keen to share their opinions.

This teacher sure had a perfect class, but there was a back story. The teacher asked many questions, but not everyone in the class knew the answers. However, they all had their hands raised.

Before lesson time, the pupils already got accustomed to some set of rules. They were instructed to all raise their hands whenever the teacher put forth questions.

It did not matter if they knew the answer or not. There was, however, a trick to deciphering who knew the answer: everyone who knew the answers raised their right hands.

The pupils who had wrong answers raised their left hands. Through this, the class teacher was able to choose a different kid every time, and the answer was always correct.

Read another riddle here.