My History class

Yesterday I had to give a lesson to the Year 3 in History. The teacher of history should have given his first introductory lesson, but when he started he messed up because of the anxiety.
 His voice started to tremble and went down. Fortunately, the class was not too disobedient. A few boys were misbehaving, though.
 Seeing the situation,  I proposed to read the materials instead of the teacher. He didn't mind.
 For the record, he is a young man who seems to have just finished the university and never given any lessons at school.
 So I took matters into my own hands and I've quickly read the teacher's syllabus.
 There were basic terms such as a century, a millennium, a year, a month, an hour,  mankind, genealogy, a family tree. My class studied this last year.
 The teacher started with the definition of the word  year and said that a year is a time interval in thirteen months. That's when I suspected something was wrong. After that, he repeated the same phrase one more time. After giving the definition, he repeated it about ten times, but with the correct number of months, which is twelve. I sat at the first desk, right in front of him and I asked him if he wanted to switch roles with me.
 He simply told me, "If you want to give a new topic on record, feel free!"
 I used his notes and dictated the definitions to the class. A few pupils in the back desks were talking and throwing pieces of papers at each other. I have a loud and confident voice, so it sounds perfect for teaching. I raised my voice and told to the urchins to stop it and shut up.  I sounded very threatening, so it worked.. Everyone drowned into the silence and started to write.
 After class, I told to the students to write down their homework in their planners. Almost everyone did it!