I was 13-years-old and it was “games” day: rugby. It was every Tuesday afternoon come rain, sleet or snow. I dreaded it every single week but I remember one particular Tuesday as clear as day.

Mr Klein was a stand-in PE teacher, he was retired and used to help out occasionally.

On one particular day, we were stood in a circle doing a warm-up in front of the changing rooms. I don’t remember the whys or whats, but I remember Mr Klein shouting, very aggressively: “Oi, Ginge. Do 20!”.

I remember all my peers laughing hysterically as I ran into the middle of the circle feeling utterly humiliated and “did 20”.

And then we carried on with the warm-up and I remember nothing more from that day, week, month, maybe even year. Yet I remember that incident because of the way it made me feel.

I’m not an overly sensitive person, by the way; having ginger hair and going to an all-boys school in Birkenhead, you really can’t be. I think it’s the fact it was a teacher, someone in authority and that was in front of my peers. Maybe he saw it as banter? Maybe it was?

Either way, I remember it, for all the wrong reasons. I remember that incident more than most of the lessons I was taught at school.

When I was 10, I had a fantastic teacher called Mrs Keaton. But wow, could she be scary. 

For some reason, and again, I can’t remember the how’s and whys, I called another student a “coward”.

The student was upset and had told Mrs Keaton who promptly took me to the school hall and gave me a right dressing down.

I disctintly remember sobbing my little guts out. Her final words were: “Never call anyone a coward again.” I didn’t because I always remembered those six words.

The moral of these two stories is this; as teachers, we have the most staggering power to make a lasting impact, good or bad, on a person’s life and its path. And our most potent weapon in making that impact is our words.

We make hundreds of comments to students every day, often without even thinking. We trust ourselves, and so we should. We are professionals with good intentions.

But it’s also worth considering that one throwaway remark, made from a good place, can be remembered, forever. It can create its own legacy.

Children, regardless of how some appear, have the most impressionable of souls.

When, in 1895, Albert Einstein’s teacher told him he will “never amount to anything”, do you think he remembered? Do you think it inspired him to more?

When Charlotte Bronte was told that she “writes indifferently”, did it make her want to prove them all wrong?

These examples are the biggies, but it’s the smaller remarks that can devastate or elevate too. I love what the award-winning director Michael Winner, said about his English teacher:

“When I was 17, I went to a private tutorial establishment that was based in Buckingham Gate and Guildford, and met the greatest educationalist I have ever met. Her name was KM Hobbs. She wrote to my parents and told them I was illiterate. She said, “If you think your son is ­going to get into Cambridge, you’ll have a long wait.” Within a year, I had passed the ­necessary exams and I was a student at Cambridge, still at the age of 17. She turned a moron into something close to a genius. That was a great achievement.”

See - 16 words - and what an impact they had. Michael Winner started working, because of Ms Hobbs.

The thing is, you don’t know who you are speaking to: it could be a future prime minister, a future professional footballer, a future noble prize winner and so on. You could be talking to someone who is going to have the toughest of lives and your words, your few, little, seemingly insignificant words, could hold them up in the future when they might sink. Propel them to carry on the fight.

Of course, we are human and we all make mistakes. We all have to make decisions, day in, day out, on what to say and how to say it. We can’t get it right all of the time.

But this article isn’t about that. This article is about the privilege we have in being able to positively change the trajectory of a mood or an idea or an attitude every single day.

There’s not many people who can say that about their jobs. It’s worth remembering, just like I remember what Mr Klein said in 1998.

Thomas Rogers is a teacher who runs rogershistory.com and tweets at @RogersHistory

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