Category Archives: Classroom

Practice, Experience, Learn!

I’ve heard people say “I wish I knew then what I know now”. The statement points to the fact that we are constantly gaining new knowledge and skills. This doesn’t just happen in school of course.

Students often say (and think) that the set work is too hard. But I tell them that whenever people first try to to do something, they might not be that good at it. However, through practice they get better. We learn as we go.
Recently we had a tree cut down in our front yard and we decided to keep the wood for our fireplace. The tree fellers left the wood in roundish pieces which I could chop up.
The last time I chopped up wood, I used an axe but the axe kept getting stuck. Someone mentioned that I should use a block splitter, which is like an axe but with a wide blade that pushes the wood apart as it moves downwards.
So I bought one and WOW! It works so much better. If only I knew then what I know now!
I have also discovered over the past week that bringing the block splitter down between the rings of the tree works better than trying to cut across the rings.
I’m obviously not an expert wood chopper but it’s amazing how often I do something for the first time and I don’t do it very well, but then I get better through practice or learn some new trick that makes it easier. It really gives me confidence whenever I try anything new. I don’t have be brilliant at it, but I’ll improve.

Me versus I

This one simple grammatical rule is not being taught in schools but it needs to be because “me” is not a dirty word!

Let me begin with a poem.

When do we use the word I

And when do we use the word me?

When do we use the word us

And when do we use the word we?

Let me tell thee!

For some reason, younger kids say things like “me and Georgina were playing outside but then it started raining”. Their teachers and parents correct them and say “you’re supposed to say ‘Georgina and I were playing outside…’”.

However, we never then follow up by telling them when they should use the word “me”.

The word “I” is used when the person being referred to is the subject of the sentence. The word “me” is used when the person is the object of the sentence.


On the first day I went to the shop.

On the second day Georgina and I both went to the shop.

On the third day, we both went to the shop again.

Very few people get this wrong.


On the first day, the shopkeeper told me about his new car.

No-one gets this wrong either; “me” is the obvious pronoun.  A lot of people get the next bit wrong, though.)

On the second day, the shopkeeper told … Georgina and me about his new boat.

Way too many people incorrectly say “the shopkeeper told Georgina and I about his new boat”. Why should the inclusion of Georgina change the pronoun from “me” to “I”? It shouldn’t. On the first day, the shopkeeper told me something and on the second day, the shopkeeper told Georgina and me something!

We get it wrong because our teachers told us (correctly) to say Georgina and I (did something), but leave out the equally important correct use of the word “me”, leaving us, from a young age with a fear of the word me.

By the way,

On the third day, the shopkeeper spoke to us again about his new boat.

I and we go together, while me and us go together.

So, if you would normally use the word I in a sentence but there is someone with you, say Georgina and I.

If you would normally use the word me in a sentence, but there is someone with you, say Georgina and me.

Georgina and I went to the shop for a spot of afternoon tea.

When we had finished, the owner approached and spoke with Georgina and me.

Now not only are people, including teachers (!), too afraid to say “Mrs Havisham has approached Mrs Copperfield and me to offer us a pay rise for our exceptional use of pronouns…”, but they don’t even use “me” when they are talking about themselves!

I’ve heard teachers say “If you have any questions, please come and talk to Mrs Liacos or myself and one of us will help you out”.

I can talk to myself and you can talk to yourself, but you can’t talk to myself and I can’t talk to yourself. I can talk to myself and to you, and you can talk to yourself and to me. And you certainly can’t talk to myself any more than you can talk to I! You can, however, talk to me (or to Georgina and me) if you want to.

So that’s all me have to say, oops, I have to say. Don’t be afraid of me. Feel free to use me. And feel free to use the Shedding Light programs which Georgina and I created. If you have any questions, please contact Georgina or me!

Always do this before you try to answer a question on a worksheet or a test.

I would have thought it was obvious but it wasn’t obvious to (at least) three Year 11 Physics students in a class of about 20.

I had just finished teaching them the Law of Refraction using LEM’s Shedding Light on Refraction program. The bonus feature on this program explains how to calculate the angle that light will refract when it passes from one transparent medium to another. I then gave them the The Law of Refraction Worksheet. The worksheet has a list of formulas and other data. Here is a screen shot of part of the worksheet.

Question 3 asks:
A ray of light travels from air to glycerol at an incident angle of 38° and is refracted at an angle of 24.6°. What is the refractive index of glycerol?

Two students over the span of about two minutes asked the same question which was basically, “Sir, can you help me with this? I don’t know the refractive index of glycerol.”

Neither of them had read the question!!

Just as I was telling the second student that it’s the refractive index of glycerol that they needed to find, I heard another student (a third student) ask the same question to one of his mates.

I’ve been using this worksheet for years now and this had never happened before, but I thought this was a golden opportunity for an important teaching moment and I immediately stopped the whole class.
“Three students have just asked about question 3. They got confused because they didn’t know the refractive index of glycerol. This might sound a little crazy, but before you try to answer a question, you should always READ THE QUESTION first!!!”

A colleague of mine served as a Year 12 examiner for the Year 12 Chemistry exam for many years. A few years ago he told me that students routinely didn’t read the question in full before writing down their answers.
A common mistake was to answer only part of the question when the question was clearly in two parts. Another common mistake was to focus on a particular word in the first sentence of a question and then assume that the question was related to the definition of that word.

So, in summary,
STEP1: Read the Question
STEP 2: Answer the Question.

Never attempt to do it the other way around.

A Much Easier Way

What a teaching round! I recently had to supervise a pre-service teacher (what we used to call a student teacher). This was the last of three rounds that he did with me this year.
Unfortunately, I wasn’t able to let him teach the recommended number of lessons on his previous rounds because of the fact that I only work part time as a teacher. This time, however, I suggested that he teach both of my junior classes: a Year 9 class studying Heat and a Year 10 class studying Chemistry.
This would have been a huge workload because he also had to take a Maths class with his other supervisor.
To make his life easier, I suggested that he use the Shedding Light on Heat series to teach the Heat unit and the Shedding Light on Atoms series to teach the Chem unit.
So, on Day 1, he used Shedding Light on Heat Episode 2: Changes of State and its accompanying worksheet to teach the class why things change state. The explanation side of the teaching was taken care of by the video with animations, actual footage, and explanations. The students then used their memories and the online text book on the Changes of State page to answer the questions.
It was so easy!
I’ve seen plenty of pre-service teachers struggle to explain things verbally while using white-board markers and hand-drawn diagrams. Unfortunately, I’m also guilty of giving students less-than-satisfactory explanations that take too long. 🙁 A short sharp video, though, can take care of the explanations, which frees up a lot of time so that students can get on with actual learning activities.
The pre-service teacher also started teaching my Year 10 class about electron shells using Shedding Light on Atoms Episode 6: Electron Shells. Once again it was so much easier than legacy approaches.
By the end of his round he had taught the Year 10 class about electron shells, covalent bonding, and ionic bonding. During lessons, he would move around the room helping students who needed additional support.
He didn’t use just the Shedding Light programs, though. Interspersed throughout his round he organised a whole lot of pracs and a few mini-assignments. He also regularly asked students to read out their answers to the class, something I always do when I’m teaching to encourage better literacy. See The First Thing I Tell A New Class.
The reason LEM started making the Shedding Light videos was on full display during the teaching round. A good video makes it easy for any teacher, regardless of expertise, to communicate science concepts easily and effectively to their class, especially when the video is accompanied by learning activities and pracs.
The work the students did during the teaching round was of a very high standard. The pre-service teacher regularly collected it and then gave feedback.
Overall, he ended up teaching about twice as many periods as he needed to since the Shedding Light programs helped him in quite a few of them.
So, whether you are a beginner or an old hand experienced, try using a Shedding Light program to teach your class. They are available to schools that have ClickView, Learn360, Films on Demand, and SAFARI Montage, or you can order directly from the LEM website.
I wish the pre-service teacher, and you, dear reader, every success.

The First Thing I Tell A New Class.

Hi everyone. My name is Mr Liacos and I’m going to be your Science teacher this year. I’m hoping that you’ll enjoy Science. We’re going to do pracs, theory work, assignments, and other things, and by the end of the year you’ll know a lot more than you do now!

Now even though I’m your Science teacher, I also consider myself to be one of your English teachers. Probably the most important thing you learn at school is reading and writing, and even though you can all read and write, the more practise you get, the better you get.

So, I like Science and I like learning about Science (I became a Science teacher after all!), and I’m hoping you like Science too, but even if you don’t, I want to use the time in class to keep developing the two most important skills that anyone learns in school: reading and writing. You will use your English skills for the rest of your lives in every aspect of your lives.

So, whenever you’re answering questions, or writing down the observations you made in a prac, or completing an assignment, I don’t want you to concentrate just on the Science, but also on the English. I want you to try to write everything in your best English.
I don’t just want a correct answer, I want a well-written correct answer!

What I’m going to do is regularly ask you to read out what you’ve written to the rest of the class and I want to comment not just on whether your work is correct but also on the English. This way you get to practise your English more AND you’ll be able to teach others about the work we’re doing. You’re not just going to learn stuff from me, but you’re going to learn stuff from each other. This class is a learning community, and we are all going to contribute to everyone’s knowledge.

Finally, let me say this. Quite often, kids used to say to me, “Sir, I get it, why do I have to write it down?” The science is often the easy part. It’s the English, the good English, the well-expressed English that is the difficult part. But it’s the most important part and the part that cuts across every subject and it’s the part that will help you more than any other part. So do your best. I’m looking forward to a good year.
So let’s begin…

Note to Teachers:
After, say, a prac, I usually get 4 or 5 kids to read out their answers to Question 1. I then give some quick feedback to each student after they’ve read out their answers. I then get 4 or 5 kids to read out their answers to Question 2, and so on. This takes a bit of time, but it’s worth it.

Quite often, I get them to write out a summary of the whole prac: what the aim of the prac was, what they did, their findings, the scientific explanation of their results, and how the prac relates to real-world scenarios. I first ask them to suggest some key words that they might want to use, and I write those words on the board. They then wrote their summaries and 5 or 10 minutes later, I select a few of them to read out their answers.

So, for example, they might write:
In this prac, we investigated the expansion of metals when they’re heated. We attached one end of a metal rod to a retort stand and placed the other end above a pin with a straw stuck through it. We found that the metal rod expanded a little when it was heated because as it expanded, the pin rolled forward and the straw position changed. The metal expanded because the atoms were vibrating faster and so they took up more room. When the metal rod cooled down, the metal contracted. Engineers have to take the expansion and contraction of metals into account when they design bridges and buildings.
(see the instructions for this prac here.)

I’ve been teaching like this for quite a few years now and it has been received very positively by my students. They get to show off their work to the rest of the kids, they get to hear “best-practice” answers from other kids which lifts everyone’s standards, and kids who may not have understood something first time get to hear the answers from their peers. Everyone wins. And that’s how classes should be!

After watching a Shedding Light program, I do the same thing with the worksheet answers. Students are asked to read out their answers. This reinforces the fact that what they write has to be understood by an audience, they practice their English, and they all learn from each other. And they’ve all got a much higher chance of learning a concept if they’ve heard it 4 or 5 times!

I am totally convinced that by emphasising literacy, but surrounding literacy within the context of Science, my students learn both better!

Epilogue: Even though I start by emphasizing literacy, it usually isn’t long before I start stressing the importance of numeracy. If you browse the Shedding Light worksheets, there are a lot of questions that require numeracy. I also make a big deal about numeracy, but I start with literacy.
So, try it out!

Still Useful Four Decades Later

For a long time, teachers taught knowledge that they had acquired to students who had not yet acquired it.
With the internet, we are no longer necessarily taught by teachers who are in a classroom with us, but we can easily search for, read up on, and learn stuff from people anywhere on the planet.
This is my first blog post that I’m writing just to test out the software. No-one has directly taught me how to do it, but I am indebted to the many talented people who have written fantastic articles on the internet describing how to set up blogs and websites.
Having said that though, I couldn’t have done anything without the ability to read, to write, and to do mathematics, and these things I learned from my teachers.
So, if I learned how to set up a website (and to make Science videos) without actually attending a class for these things, what role will there be for teachers in the future (beyond teaching the basics)? With the amount of information on the internet, do we need teachers anymore? Well, text books have been around at least since 1980 when I started high school (and I’m told even earlier, but who cares, right?), but my teachers were still an essential part of my education.
The way kids (and all of us) learn stuff has changed a lot (and it will continue to change a lot). The use of videos, for example, has exploded over the past 10 years because it is now so much easier to show them from a computer. A lot of teachers are using the Shedding Light videos to take care of the actual instructional side of things.
However, students still need great teachers to guide them, to encourage them, to set high standards, to help them to set goals, to give feedback, and to teach them the skills that they do not yet know that they will need in the future.
Interestingly, when my teachers taught me to read, to write, and to do maths, I did not realize just how useful those skills would be even decades later. A lot of what we learn is like that.
So, teachers are invaluable!