0:00:03 > 0:00:05# There are lots of things
0:00:05 > 0:00:07# All around us
0:00:07 > 0:00:10# Exciting things that surround us
0:00:10 > 0:00:12# But how does it work?
0:00:12 > 0:00:14# Do you know?
0:00:14 > 0:00:15# How is it made?
0:00:15 > 0:00:17# Do you know?
0:00:17 > 0:00:19# Things that go up
0:00:19 > 0:00:20# Things that go down
0:00:20 > 0:00:22# Things that go pop
0:00:22 > 0:00:23# Things that go round
0:00:23 > 0:00:25# With special cameras
0:00:25 > 0:00:27# To show you inside
0:00:27 > 0:00:30# It's going to be a big surprise
0:00:30 > 0:00:32# But how does it work?
0:00:32 > 0:00:34# Do you know?
0:00:34 > 0:00:35# How is it made?
0:00:35 > 0:00:37# Do you know?
0:00:37 > 0:00:39# Do you know?
0:00:39 > 0:00:40# Let's find out! #
0:00:44 > 0:00:48Hello, I'm Maddie, and today I'm getting ready for a birthday party.
0:00:48 > 0:00:52Have you been to a birthday party? They're really fun, aren't they?
0:00:52 > 0:00:55Birthdays can be celebrated in lots of different ways.
0:00:55 > 0:01:00You might play fun birthday games or sing birthday songs or
0:01:00 > 0:01:02eat special food.
0:01:02 > 0:01:06But, there's something else that you might find at a birthday party.
0:01:06 > 0:01:07Can you guess what it is?
0:01:07 > 0:01:10That's right, it's a cake.
0:01:10 > 0:01:14One of my favourites is called Victoria sponge.
0:01:14 > 0:01:17I love all of the jam and cream inside it.
0:01:17 > 0:01:20And these bits are called sponge.
0:01:20 > 0:01:23Sponge is made from lots of different ingredients,
0:01:23 > 0:01:25like milk, flour, butter,
0:01:25 > 0:01:28eggs and sugar.
0:01:28 > 0:01:32But do you know how sponge becomes thick, lovely and bouncy,
0:01:32 > 0:01:34just like this?
0:01:34 > 0:01:37How does a cake work?
0:01:37 > 0:01:38Let's find out.
0:01:43 > 0:01:45To show you how a cake works,
0:01:45 > 0:01:48I'm going to bake a cake for the party.
0:01:48 > 0:01:54Now, I need to mix all of our ingredients together in a big bowl.
0:01:54 > 0:01:57In goes the sugar with the flour,
0:01:57 > 0:01:59and then the butter.
0:01:59 > 0:02:01And now, for the fun bit -
0:02:01 > 0:02:02cracking the eggs.
0:02:04 > 0:02:05And the milk.
0:02:07 > 0:02:10Oh, and we mustn't forget this.
0:02:10 > 0:02:12This is called baking powder
0:02:12 > 0:02:16and it's a special ingredient that will make sure our cake rises
0:02:16 > 0:02:19in the oven.
0:02:19 > 0:02:24Now, we need to mix all our ingredients together.
0:02:24 > 0:02:27And for that, we need an electric whisk.
0:02:27 > 0:02:28Watch this.
0:02:28 > 0:02:29WHIRRING
0:02:30 > 0:02:32Because it works really quickly,
0:02:32 > 0:02:36it's going to put lots of air bubbles into the mix.
0:02:37 > 0:02:38WHIRRING
0:02:38 > 0:02:41Listen to the sound of the electric whisk.
0:02:41 > 0:02:43WHIRRING GETS LOUDER
0:02:43 > 0:02:46It's like an aeroplane taking off.
0:02:51 > 0:02:53OK, have a look in my bowl now.
0:02:53 > 0:02:57Can you see that all of the different ingredients have
0:02:57 > 0:03:00been mixed together into a smooth, runny mixture?
0:03:05 > 0:03:08I'm just pouring our mixture into two cake moulds,
0:03:08 > 0:03:10ready to go into a hot oven.
0:03:13 > 0:03:15The oven is hot.
0:03:15 > 0:03:18You should never go near a hot oven yourself -
0:03:18 > 0:03:20always ask a grown-up to do it.
0:03:24 > 0:03:27When cake mix goes into a hot oven,
0:03:27 > 0:03:29it starts to bake.
0:03:29 > 0:03:32It will rise and get bigger and bigger and turn into
0:03:32 > 0:03:36a tasty sponge, but to find out how, we need to get a closer look.
0:03:38 > 0:03:42When the ingredients are mixed together, they start to change.
0:03:42 > 0:03:45This is called a chemical reaction.
0:03:45 > 0:03:49First, the baking powder and the milk start to react together,
0:03:49 > 0:03:51making bubbles of air.
0:03:51 > 0:03:54The air bubbles are surrounded by a layer of fat
0:03:54 > 0:03:58from the butter, which traps them inside the mixture.
0:03:58 > 0:04:02Then, when the mixture goes into the oven, the hot air inside
0:04:02 > 0:04:06makes the egg white surround each bubble and go hard.
0:04:06 > 0:04:10This protects the bubbles so that they don't burst.
0:04:10 > 0:04:12As the mixture heats up more,
0:04:12 > 0:04:16the trapped air bubbles start to get bigger.
0:04:16 > 0:04:19As they grow, the flour in the mixture around them starts to
0:04:19 > 0:04:25stretch. It stretches and stretches until it can't stretch any more.
0:04:25 > 0:04:27And by then, the cake is ready.
0:04:28 > 0:04:30It's really clever, isn't it?
0:04:30 > 0:04:34My cake takes 20 minutes to bake, so I'm going to use my special
0:04:34 > 0:04:38camera to do something called a time-lapse.
0:04:38 > 0:04:41This means we can film something that takes a long time,
0:04:41 > 0:04:45but when we watch it back we can see it happening really quickly.
0:04:45 > 0:04:47Right, the camera is in place,
0:04:47 > 0:04:52so we've got to wait 20 minutes until the cake is ready.
0:04:52 > 0:04:58You can see how the cake mixture is very flat to start and now watch...
0:04:58 > 0:05:00Look how the cake is growing.
0:05:03 > 0:05:05TIMER ALARM RINGS
0:05:06 > 0:05:08I think it's ready.
0:05:10 > 0:05:11Perfect!
0:05:13 > 0:05:14Sponge number one.
0:05:18 > 0:05:20And sponge number two.
0:05:20 > 0:05:27The sponges have got so much bigger and they smell fantastic.
0:05:27 > 0:05:28Look.
0:05:28 > 0:05:30They've risen by about this much.
0:05:30 > 0:05:33That's three centimetres.
0:05:33 > 0:05:36Now, I just need to add the finishing touches to our cake.
0:05:38 > 0:05:40I loved seeing how cake works.
0:05:40 > 0:05:43What was your favourite bit?
0:05:43 > 0:05:47Do you remember the special ingredient that made the cake rise
0:05:47 > 0:05:49when it reacted to the milk?
0:05:49 > 0:05:50It's baking powder.
0:05:51 > 0:05:54Did you hear the sound of the electric whisk?
0:05:56 > 0:05:57WHIRRING
0:05:59 > 0:06:02And did you see the way the cake rose in the oven?
0:06:10 > 0:06:13So, now you know how a cake works.
0:06:13 > 0:06:17And you know all about the special chemical reaction that
0:06:17 > 0:06:21happens inside the cake, and how the air bubbles make the cake rise.
0:06:21 > 0:06:24And, if we cut into the cake, you'll see that the air bubbles
0:06:24 > 0:06:28are still there, and that's what makes the sponge nice and fluffy.
0:06:30 > 0:06:33Can you see all of the little air bubbles?
0:06:33 > 0:06:37This cake looks like it's going to be yummy.
0:06:37 > 0:06:39I love having parties at my house,
0:06:39 > 0:06:42but you can have parties in lots of different places.
0:06:42 > 0:06:45In the garden, in a park, a swimming pool.
0:06:45 > 0:06:49I can think of another place you might have a party.
0:06:49 > 0:06:51Do you know what it is?
0:06:51 > 0:06:53It's a soft play centre.
0:06:53 > 0:06:54Brilliant!
0:06:56 > 0:07:00I like crawling through the rollers and running through the tubes.
0:07:00 > 0:07:02And...
0:07:02 > 0:07:03playing in the ball pool!
0:07:03 > 0:07:06But, do you know how all of these things in
0:07:06 > 0:07:09a soft play centre are made?
0:07:11 > 0:07:12Let's find out!
0:07:18 > 0:07:22To find out, I've come here, to a soft play factory.
0:07:25 > 0:07:27They make lots of soft play items here.
0:07:27 > 0:07:31They come in different shapes and sizes, lots of different
0:07:31 > 0:07:35bright colours and, of course, they're all soft - even the floor.
0:07:36 > 0:07:39Let's see how they make the floor.
0:07:40 > 0:07:42Like all the soft play items made here,
0:07:42 > 0:07:45the floor pads start off with this.
0:07:45 > 0:07:47It's a material called PVC.
0:07:47 > 0:07:49It's really shiny, isn't it?
0:07:50 > 0:07:54This is Sarah and she's going to cut out all the pieces we need
0:07:54 > 0:07:55to make a floor pad.
0:07:57 > 0:08:01She starts by drawing a big square on the PVC.
0:08:01 > 0:08:04This will be the top of the floor pad.
0:08:04 > 0:08:06The square is then cut out.
0:08:06 > 0:08:09Listen to the sound of the scissors.
0:08:10 > 0:08:11SCRAPING
0:08:13 > 0:08:16Next, Sarah cuts out the bottom of the floor pad
0:08:16 > 0:08:18and then the sides.
0:08:23 > 0:08:27Once all the pieces have been cut out, they need to be sewn together.
0:08:29 > 0:08:31And that happens here.
0:08:32 > 0:08:34Maria is going to use a sewing machine to
0:08:34 > 0:08:37sew all the pieces together.
0:08:40 > 0:08:44Maria is sewing the floor pad inside out.
0:08:44 > 0:08:47She does this so that when it's turned the right way out,
0:08:47 > 0:08:51all of the stitches are hidden and it looks lovely and neat.
0:08:53 > 0:08:57The zip, here, is where the filling is going to go inside.
0:08:57 > 0:09:02It's a bit like a bigger version of a cushion cover on a sofa.
0:09:02 > 0:09:04To make the floor pad soft and squishy,
0:09:04 > 0:09:09the skin is filled with a material called foam.
0:09:09 > 0:09:11There are a lot of different types of foam,
0:09:11 > 0:09:15but this is the foam that they use for a floor pad.
0:09:15 > 0:09:19Can you see that, when I squeeze it, it's soft and squishy?
0:09:19 > 0:09:22Let's use my special microscope camera to get
0:09:22 > 0:09:24a closer look at the foam.
0:09:27 > 0:09:29Whoa, look at that!
0:09:30 > 0:09:32That is incredible!
0:09:33 > 0:09:37Can you see that there are lots and lots of tiny gaps?
0:09:37 > 0:09:40Well, those gaps are actually bubbles of air
0:09:40 > 0:09:44and it's the air that makes the foam soft and squishy,
0:09:44 > 0:09:46so it's safe to play and jump around on.
0:09:50 > 0:09:52Before the foam can be put in the cover,
0:09:52 > 0:09:55Colin turns it the right way round.
0:09:55 > 0:09:58Look, now all the seams are hidden inside and the edges
0:09:58 > 0:10:01look really neat.
0:10:01 > 0:10:05Now the foam can go inside the cover.
0:10:05 > 0:10:07The foam has to reach every little corner,
0:10:07 > 0:10:09but Colin makes it look easy.
0:10:11 > 0:10:12Brilliant!
0:10:12 > 0:10:16All zipped up, and here we have one finished floor pad.
0:10:17 > 0:10:21But, a soft play centre needs more than just floor pads.
0:10:21 > 0:10:24This is a parrot you can sit and rock on, like this.
0:10:24 > 0:10:26It's really fun, isn't it?
0:10:26 > 0:10:28Shall we see how the parrot's made?
0:10:28 > 0:10:29Let's find out.
0:10:29 > 0:10:33The rocking parrot is made with the same PVC material - the only
0:10:33 > 0:10:37difference is that, this time, Sarah is going to use a template.
0:10:37 > 0:10:39This is a template.
0:10:39 > 0:10:43Can you see it's the same shape as the rocking parrot?
0:10:44 > 0:10:48The template is placed onto the material and Sarah draws
0:10:48 > 0:10:49around it with a pencil.
0:10:51 > 0:10:54She then uses a tool called a scalpel
0:10:54 > 0:10:56to carefully cut out the shape.
0:10:58 > 0:11:00So, to make the parrot,
0:11:00 > 0:11:04there are two side pieces like this one and the top part, where you sit.
0:11:04 > 0:11:09But, the rocking parrot also needs some smaller pieces like...
0:11:09 > 0:11:11the eyes and...
0:11:12 > 0:11:14..a beak and...
0:11:15 > 0:11:16..the wings.
0:11:16 > 0:11:19But the wings look a little plain, don't they?
0:11:25 > 0:11:28Tony is doing something called airbrushing,
0:11:28 > 0:11:30to finish off the wings.
0:11:30 > 0:11:34The airbrush sucks up paint through tube into the nozzle.
0:11:34 > 0:11:37Then, air is blown through the nozzle to put paint
0:11:37 > 0:11:39out the end in a fine mist.
0:11:41 > 0:11:45Tony now glues the smaller pieces onto the parrot's body.
0:11:47 > 0:11:51It's really starting to look like a parrot now.
0:11:51 > 0:11:53And then all the pieces are sewn together.
0:11:55 > 0:11:57Now, the parrot is ready for the next stage.
0:12:00 > 0:12:01Thank you.
0:12:03 > 0:12:07Colin's turning the parrot cover the right way out.
0:12:07 > 0:12:09Do you remember what we need next?
0:12:09 > 0:12:11That's right, it's the foam.
0:12:12 > 0:12:16But, which bit of foam should we use for the rocking parrot? Hmm?
0:12:18 > 0:12:20This one. It's nice and squishy.
0:12:24 > 0:12:27All Colin has to do now is put the foam inside the cover.
0:12:29 > 0:12:31It's a bit of a squeeze.
0:12:41 > 0:12:43And there we go.
0:12:43 > 0:12:45One finished parrot.
0:12:45 > 0:12:49It looks great, doesn't it? Ready for someone to play on.
0:12:51 > 0:12:55What was your favourite bit about seeing how soft play items are made?
0:12:55 > 0:12:59Do you remember the name of the material used to stuff
0:12:59 > 0:13:01the floor pad and parrot?
0:13:01 > 0:13:03That's right, it's called foam.
0:13:04 > 0:13:07Did you hear the sound of the scissors as they cut
0:13:07 > 0:13:09the PVC material?
0:13:09 > 0:13:10SCRAPING
0:13:12 > 0:13:15And did you see all the air bubbles when we looked at the foam
0:13:15 > 0:13:17with my special camera?
0:13:23 > 0:13:27And so, the next time you come to a soft play area like this...
0:13:27 > 0:13:28Whee!
0:13:28 > 0:13:30..you'll know how it's made.
0:13:31 > 0:13:33And now you know how cakes work,
0:13:33 > 0:13:38so you can tell all your friends and family about the chemical reaction
0:13:38 > 0:13:40that happens inside the cake to make it rise.
0:13:41 > 0:13:43Woohoo!
0:13:45 > 0:13:47See you next time!
0:13:50 > 0:13:52# There are lots of things
0:13:52 > 0:13:54# All around us
0:13:54 > 0:13:57# Exciting things that surround us
0:13:57 > 0:13:59# But how does it work?
0:13:59 > 0:14:00# Do you know?
0:14:00 > 0:14:02# How is it made?
0:14:02 > 0:14:04# Do you know?
0:14:04 > 0:14:06# Do you know?
0:14:06 > 0:14:07# Let's find out! #