And I'm Possum.
Come on in.
Oh hello, everyone.
I'm here to see Skip, because I want to see his marble run.
So Possum, what brings you here so early in the morning?
Well, see my things here?
I've had a few ideas, but I'm stuck, and I need some help, so I thought your marble run could give me some ideas.
Well, everything's been going very well, and today could be the big day.
Does that mean it's a big, exciting day?
Yes, I think this could be the day we get the marble run to work.
Oh, hang on, Sally's here.
Oh hello, everyone!
Oh Skip, Possum was so excited about your marble run.
I am too.
Sally, Skip says he's almost finished.
Oh, that's great!
Yes, everything's just about ready.
I've just got one little problem.
This ball should be rolling down there but it's getting stuck and I don't know why.
It's really puzzling me.
Oh Skip, I could help you.
I can just pick it up and move it.
Possum, do you think Skip would feel that he had solved the problem if you had to carry the ball over the gap?
Skip will be a bit disappointed, wouldn't he?
The ball should just roll down by itself.
Gravity should make it go.
If I stop that, it won't work.
You're right, though, gravity is what's at work here.
If you have a look, the ball is being pulled down by gravity.
Oh, but how does it start because I know when I've got my soccer ball, it doesn't start rolling by itself.
I have to kick it to make it move.
You need something to make it move.
It's me, pushing it.
You are using force.
If you kick it hard, it's going to move fast, and if you just gently tap, it's not going to go very far.
We're talking about a trigger, or a switch and that's what makes it start.
The trigger on this is a little lever.
The lever goes down, and the next marble starts to roll.
You've given me some great ideas Skip.
Now I think I know what I need to do!
Sometimes it can be hard to solve the big problems, so if you solve the little problems first, that can make it easier to solve the big problems.
Oh yes, you're right!
I just have to think things through.
Yes, it's very important to think creatively, and then you can pick the good ideas to make it work.
Oh, this is great.
I can see some wonderful ideas, I can see how that part goes, and then that makes that happen next and then it's finished!
That is called a chain reaction.
You're right because one action makes the next action happen, and on and on.
Sally, what does that mean?
Oh, well, a chain reaction is when one action starts the next action, and that one starts another one after it, and so on and so on.
How about I show you?
You stand in the middle Possum.
Ok, straight line.
I'm going to start this by pushing you.
Oh, I get it now.
Why don't we watch some children learning about chain reactions using dominoes?
Yeah, let's watch!
That was fantastic and that's given me some great ideas.
I think I know what I need to do now but, Skip, can you show me how the marble run works?
Now, Sally, do you think you could work out how it all starts?
Do you have water in this?
Yes, I do!
Right, now, well, something would fall into this bucket.
That would pull the watering can, the water would start to trickle, flow down through here, into this bucket.
That would fill up, and then when it gets heavy, it would pull the string, and the marble would start to roll.
Yes, you're spot-on!
This is giving me some fantastic ideas.
Oh, that's great and I think I might have found the solution to the problem I had earlier.
Well, I better get back.
I have a few things I need to do.
When can we come back and look at your marble run?
I'll let you know by flashing my light.
If you look from the top of your tree, you'll see the light at the top of my crow's nest.
If it's flashing, it means the marble run is ready and you can come over.
Alright, let's go!
Ok, let's go.
I've been watching Possum working on his experiment.
I can see that he's trying to work out what to do next.
I think he's trying to make something like Skip's marble run.
I can see that he's thinking very hard and he always comes up with a creative way to solve a problem.
Have a look!
This is my chain reaction.
Well, you've got some very interesting ideas here, Possum.
Can you tell me how it works?
Well, I've learnt so much about levers and the ball rolling from seeing Skip's marble run.
His is so good and I want mine to be great too.
Well, I can see your ramp and that the ball will roll down it, so that's great.
Skip's marble run was so good, the way he made it.
So I want to make mine just as good as his.
I can't wait to go and see his marble run.
Why don't we go there now?
No Sally, we can't go yet.
Remember, Skip said we have to wait until we see the flashing light.
That means I'll have to wait, then.
Yes, that's right
Now, let's see.
Hmm, hat ball…
Ah, I've got it!
Ooh, what is it?
Oh, I won't tell you yet Sally but once you see it, then you'll understand.
Oh ok, that's great.
Now, I'm going to go to the top of my tree and see if Skip's light's flashing.
OK, off you go.
The light isn't flashing.
The light's flashing!
I'm going to tell Sally.
Skip's light is flashing!
Let's go, come on.
Aha, good, good.
Oh, oh, come in, come in.
It looks great.
You've got here just at the right time!
We've been watching your crow's nest all day and when we saw the light flashing, we knew you were ready, and we ran on over.
Oh Skip, I'm so excited, I can't wait.
Can we do it now?
Hm, just a moment, Possum.
Where is my coffee?
Oh, surely your coffee can wait Skip.
Can't you show us the marble run?
Oh, is an important part.
Right, are you ready?
Come over here.
Now, I pull this to make it start.
Oh, quick, over here, quick.
Look at that one.
Oh, and that one.
Oh, oh, look, look.
Look, over here.
That was great!
Oh, that was so amazing.
Oh, Skip, I love the way you make coffee.
Oh, I really enjoyed making this.
I know it's a bit silly just for a cup of coffee, but it was a lot of fun making it.
Oh, it's been a lot of fun to watch this. I really enjoyed it.
Wow, and that goes around and around and around.
Oh, you've done such a good job.
Oh, this is great work. Look at that.
Ooh, ooh, ooh, ooh, ooh…
Oh, thank you.
I think it's the best one I've ever made.
I love it.
This is so very big!
I didn't make this one.
What's this for?
This is the trigger.
That is what makes it start.
Oh yes, I see, it starts it off and, Skip, you may pull the trigger.
Me but, before you do, make sure you're ready to run and follow the ball.
Oh, ho, this is very exciting.
Ooh, come on, come on.
Oh, that was great.
That was really good.
Possum, you've made such a wonderful thing here.
You've been very creative making your chain reaction.
Oh, it is wonderful.
Oh, thank you, thank you.
I really enjoyed this.
It's been such a fun day.
Oh, yes, it was a great day, wasn't it?
Well, our time is up.
Thanks for watching.
See you next time!
Let's do it again.
Oh, yes – let's go!
Skip has been working on something amazing and now it is time to see it in action, but Possum has been busy too. Watch carefully!