1. BIG BANG NOTES!
This is the introduction page of the notes. If you click on the small blue dot the phrase “Big Bang Notes!” appears in a starburst. If you click on the starburst then the phrase collapses back into the ball. I like to do it two or three times for effect before clicking to the next screen.

2. Our sun is born, the heavy elements around it clump into planets
TIMELINE
Modern Times
5 BYA
13.7 Billion Years Ago (BYA)
Simple life evolves on Earth
Your teacher is born
The beginning of the universe
3.8 BYA
I start this page by asking the students “What is this?” Usually someone will answer that it is a timeline, to which I reply “This is a timeline of the universe. It highlights the four most important moments in history.” I then reveal the four points and talk briefly about each one as they copy it down on their notes.

3. The big bang theory is a theory about…
a. What the universe was like in the beginning
b. What’s happening in the universe now.
This slide is pretty straightforward. I have them copy it into their notes. I emphasize that the big bang theory doesn’t just talk about the beginning of the universe, it also explains why the universe is the way it is today.

4. The Universe Today The Universe 1 million years ago
Going along with their notes I tell them that there are three important things that I want them to remember about the big bang. As the slide begins a yellow blob shows up with the words “the universe today”. I ask them, if this is the universe today, do you think the universe yesterday was bigger or smaller than it is today? How about 10 years ago, bigger or smaller? Then I move on with the PowerPoint showing the universe getting progressively smaller as you move back through time. It’s like watching the history of the universe in rewind.

5. 1. The universe is expanding and has always been expanding since it began.
The Universe Today
I have the students write down the words that appear at the top of the screen. I emphasize here that the big bang was not actually a “bang” at all. There was no explosion, just an explosive expansion, triggered by some unknown event. I like to start with the idea that the universe is expanding because it leads well into why we believe that the universe used to be a very small place. As you click the button all of the other layers of the universe fade away leaving just the small universe from way back when. I discuss this with the students explaining that if the universe was bigger now than it was 10 million years ago, and it was constantly getting smaller as you go back in time, then you come to a time when the universe was very small. Incredibly small. As hard as this is for us to wrap our brains around, the universe was at one time small enough to fit in this room. Can you imagine how dense that would be? What would the temperature be like in such a dense place? Imagine if we packed 300 students into this classroom – what would happen to the temperature. So, the next thing that I want you to remember about the universe is that…

6. 2. In the beginning the universe was very small, hot, and dense.
…in the beginning the universe was very small, hot, and dense. Have them write this in their notes and then answer, as best you can, any questions that they might have.

7. 3. As the universe expands, it is also cooling down over time.
Before I get into the third thing and start talking about this slide I have the students go ahead and first fill out the part below that says “What caused the big bang?” No one knows. It is still uncertain what triggered the sudden expansion of the universe from the incredibly small and dense object that it was in the beginning. Let me know if you find out. I ask the class what happens over a long period of time to something with a lot of heat and energy, just spreading out? Usually someone says that it cools down, which is what I’m looking for, butu if they don’t I like to use the (highly imperfect) analogy of a really hot bath tub. You fill it up, it’s nice and hot, so hot you can’t quite get in yet. So you decide to go to bed and take your bath in the morning. Well what’s going to happen? It will be cold. Now of course the universe is a lot more complicated than a bath sitting over night, but the same basic idea applies. Make the animation appear and then have them write down about the cooling universe in their notes.

8. 2. Universe started out small, hot, and dense
1. Universe is expanding
2. Universe started out small, hot,
and dense
3. Universe is cooling down as it
expands
I have them take one last quick look at their notes and then flip their papers over and I quiz random students about what the big bang is and the three most important things that I want them to remember about it.

9. DO HOW KNOW? WE 1. Universe is expanding
2. Universe started out small, hot,
and dense WE
KNOW?
3. Universe is cooling down as it
expands
I end the PowerPoint with the question – how do we know? This is typically where I end my first day of notes saying that this was the easy stuff. Piece of cake. Understanding the evidence is the tricky part.
I like to give a little quiz about misconceptions to end the lesson. T/F The Big Bang Theory is a theory about how the Earth was created. FALSE! We are talking the entire universe here. The Earth has only been around for 5 billion years or so, the universe is almost three times that old. T/F The big bang theory says that the Earth is getting bigger. FALSE! It says the the universe is getting bigger, that it is expanding. This does not mean that everything in the universe is getting bigger. Think of a balloon. If I blow up a balloon a little bit and then I put a peanut inside, and then I kept on blowing it up bigger and bigger, causing the balloon to expand, what happens to the peanut? Nothing! We are that peanut.