Teaching Creative Computer Science | Simon Peyton Jones | TEDxExeter

Britain stands today on the brink of
a major revolution

for the way we teach our children
about computing.

Not all revolutions are good,
but this one is. And it's being

watched with intense interest by other
countries around the world and some envy.

So I just want to tell you a little bit
about what's been happening,

why it's important and how
you can help to make it a success.

So here, let's start with something that
Richard Riley who was the Secretary for

Education in the United States
a little while ago said:

Education should prepare young people for
jobs that don't exist,

using technologies that have not
been invented,

to solve problems we're not yet aware of.

That's a big challenge, right. [laughter]
How do we do that?

So here's what we do at school.

So we teach children about skills, that's
immediately applicable knowledge,

typically involving artefacts, you know, so
you might think sowing machines, or

band saws or yes, computer programmes
like Microsoft Office ... right.

So we might teach them how to use this
stuff purposefully and that's

immediately applicable and useful but it
dates fairly quickly.

So to address Richard Riley's point,
we also teach them about foundational

discipline. So you might think about
this as long-term knowledge so stuff like

physics or history or mathematics, this
lasts you a whole life time, it doesn't

date quickly and we would use words like
'principles', 'ideas', 'techniques',

'methods', 'body of knowledge',
to describe that kind of stuff.

Now, in my field of computing, what has
happened is that the subject,

Information and Communication Technology,

which, praise be, is part of our national
curriculum up to now but has

become focused on technology, right
so it's even in the very title ...

so it's in the left-hand part of this
slide, all focused around using things

purposefullyand thoughtfully.
And that is important ... but we've

lost sight, or perhaps never gained
sight of an underlying subject discipline

which is the discipline of computer
science and perhaps that's not surprising

but even at a university level,
that's a fairly young discipline,

certainly compared to physics say.

So it's atrophied the brain (?), so I
think what we've ended up doing is,

in what we tell our children about
computing, we've ended up focusing too

much on technology, on things, on devices,
on those seductive boxes,

and not enough on ideas.

So I want our children, not only to
consume technology but to be

imaginative creators of
technological artefacts.

I want them to be creative writers as well
as appreciative readers.

I want them to understand what they're
doing, how the stuff that their using

works, as well as using it.

Arthur C Clarke once famously remarked
that any sufficiently advanced technology

is indistinguishable from magic.

And I think it's very damaging if our
children come to believe that the

computer system they're using are
essentially magic; that is ...

not under their control, made by somebody
else, not something that they can interact

with or indeed, take part in creating
with. I think that's bad.

So, if you walk up to a person
on the street today

and ask them 'what does a computer
scientist look like?' They would probably

say: 'probably male, socially challenged,
geek, spotty, probably a little bit

like Simon, actually. Well paid, maybe but
living in a basement, writing code'.

I want to encourage you, instead, to think
of computer science in the way that you

might think of science; that is as a
foundational subject that every child

should have the opportunity to
learn from primary school onwards.

That's a big shift in perception,
isn't it?

And so, to help you make that shift, I
want to just give you some idea of what

computer science is, particularly in the
context of a school.

So, here are some words, so give me some
answers to do with the study of

information and computation, not primarily
about machines at all, it should be called

computing science really.
It's about algorithms and data structures,

and the way that computational processes
communicate and coordinate. It involves

reusable skills, programming and coding,
certainly, and you will have seen a lot

in the press about why we must teach
our kids to code. But computer science

is about much more than that. It's not
just about coding to get the job done,

it's also about broader thinking skills
like computational thinking and

abstraction and modelling and design.
So these are all abstract words. I want to

show you, give you a visceral sense of
what computational information might look

like to a computer scientist.
So here is a video made by my,

the amazing Tim Bell from New Zealand
showing kids learning to sort.

So, here they are standing on a network
drawn on the floor and when two children

walk along those lines and meet at one of
the round circles, they're each holding

a number and if the kid on the left,
they swap over if one number is bigger

than the other. If they're not bigger,
they don't swap. And then when they all

start at the beginning and they do this
together, so this is a parallel algorithm

happening, they walk along the lines and
they meet and they swap over and if

everything goes right, will it go right?

Well, actually, I think it's going to
go right!

... they end up sorted, at the end.
[audience laughter]

And that, there's something rather
wonderful about that, and you can do it as

a competition, it's kind of quite fun. You
can see who can do it fastest and you can

even do it on a larger scale in a
playground. [audience laughter]

Tim tells me, this five seconds of video
took him all morning to record.

Why did I show you this? I showed you this
because it's fun, because it involves

primary school children, because it's
intriguing, right, there's something

clever happening, and it's because
there's no computers involved anywhere.

This clearly is about computation,
not about technology;

it encourages you to ask questions like:
'could we do this with more numbers?'

'Did the teacher put us in the right
order at the beginning

to end up sorted at the end?' 'Shall we
try it with a different way round?'

Do you get the idea? And some of those
questions have quite deep answers

but I love the way that a child
could ask them.

So that's about computation; let's do
one about information.

So my friend Jared, over here, supposing I
want to exchange a message with Jared,

so you probably have the idea that I could
encrypt it someway if Jared and I shared

a secret key, right, so like, marmalade -
then we could someway encrypt our message,

send it to each other and provided none of
you knew our key, you couldn't decrypt it.

But what if we didn't have a secret key
between us? Could we have a public

conversation in front of you all, at the
end of which, Jared and I shared a secret

key that we could use to encrypt our
subsequent conversation but which none of

you knew? That doesn't sound very
plausible, does it?

Because if you heard everything we said,
you'd know everything we knew.

But it's possible, it's not only
possible, it's quite easy. A 12-year-old

can understand how it's done. It's called
'Diffie-Hellman Key Exchange' and like

many of these lovely ideas of computer
science, it's immediately applicable.

When you go onto Amazon or eBay or
something and send your credit card

details, a little padlock appears on your
browser and Diffie-Hellman Key Exchange

is going on with Amazon or eBay to secure
your credentials because you don't share

a secret key yet with your supplier.
So it's a rather clever idea.

It looks superficially implausible. So
that's what I mean about

ideas, not technology. So, you might say,
alright so you convinced me recently

that computer science is kind of
interesting and maybe some kids

should do it, but should every child
do it, from primary school?

So, let me ask you this:
Why do we ask every child to learn science

from primary school? Not because
they're all going to become physicists.

So why? It's because science teaches us
something about the world around us and

that if we know nothing about the way the
world around us works,

we're dis-empowered citizens. Even when
you switch on a light, you know

that the light doesn't happen by magic,
it happens by electricity that comes along

wires, that wires can be dangerous, that
electricity comes from a power station,

that the power station burns fuel, it may
cause global warming ... all of that is

underpinned by the science knowledge that
you gained at school whether or not you're

a scientist. And so I think it's very
important that every child knows something

about the digital world that they inhabit
which is so, as we heard in our previous

talk, so infuses every aspect of our
lives. And it's not just the built world,

the artificial world, computation
increasingly helps us to understand the

natural world too. If you look at a
termite colony that builds these

extraordinary structures that architects
are still trying to figure out how did they

get so well ventilated, is there a giant
termite brain that designs that structure?

No. Somehow these little creatures
operating very simple programs in their

very simple brains, which collectively do
something amazing. And computer scientists

are very interested in working out how
that distributed computation takes place.

Other colleagues of mine at Microsoft are
working out how cells figure out whether

they're going to become kidneys or
back bones; and that's a little

computational process that's going on, you
know, in the bodies of embryos all the

time. So increasingly we're thinking of
computation of a way to understand

the natural world. And lastly, of course,
computer science give you generic thinking

skills that are useful regardless of what
profession; so analysis and design and

computational thinking are useful in any
profession. Now I know every subject likes

to tell you that but in the case of
computer science, it's true. [laughter]

So, all we have to do then, is to
establish an entirely new subject at

school - computer science. The amazing
thing is that this is not an aspiration;

this is reality.
There's been a review of the national

curriculum and as from September 2014,
there really is a new subject called

'Computing'; right, not Information
Technology any more, though it still

includes the good bits of using and
applying computers but the term covers

computer science and IT and I want to show
you, in this new curriculum, the aims.

The whole curriculum is only three pages
of A4. You can easily read it, but here

are the aims, right: Four aims. Can
understand and apply the fundamental

principles of computer science, including
logic and algorithms. Can analyse problems

in computational terms and have repeated
practical experience of writing programmes

to solve them. No other country in the
world has statements anything like as

crisp as this from, remember, this applies
from primary school onwards right the way

up to GCSEs so I think this is a big
breakthrough. So it's happening right here

and everybody else is very interested in
watching us, we're in pole position here

in the world but many other countries are
are struggling with these exact same

issues and we're all fumbling our way
towards finding a good solution. We in

Britain happen to be in that exciting and
dangerous position of being in pole

position here. So, what is the new
challenge? Well, it's no longer to change

the policy, it's to encourage and support
and equip our existing computing teachers

to do a fantastic job of delivering this
new curriculum and that's not easy.

They are motivated, they are hard-working,
they care deeply about their children but

many of them come with not enough
background in computer science because,

after all, they've never been asked to do
this before, So we have to help them.

So who is going to help them? Well, we
are. So, in the past, it would have been

the government, right, and the government
this time is standing back, they're

providing air-cover in the form of a
curriculum, they're providing some money,

but basically it's the sector; teachers,
universities, IT professionals, software

developers, the people in this room, the
people watching this video, everybody has

got to get together and help our schools
to make a fantastic job of this and to

deliver it with, not reluctantly and
grudgingly but with confidence and

enthusiasm because I think we can. So it's
actually a kind of big society thing; this

is the big society actually working.
There's a kind of creative wave of

enthusiasm. These are a whole bunch of
little groups that have grown up in the

United Kingdom and there are many others
elsewhere in the world doing similar

things in their own country that are
trying to support schools and students to

run co-clubs after school, to support and
mentor teachers and, just at the moment,

to run training courses to support
teachers. Let me tell you very briefly

about one, which is the 'Computing at
School' group which I'm chair of and

helped start a few years ago. 'Computing
at School' has been at the epicentre of

this whole exercise, it's a volunteer,
grass-roots organisation which now has

10,000 members but it was the, probably
the organisation that mainly made the

case for establishing computer science as
a component of our school curriculum and

so we're now stepping up to this challenge
of running a big programme of training

for our teachers across the country.

But it is a big challenge;
there are 3,500 secondary schools,

there are 17,500 primary schools;
and this is England alone. Scotland and

Wales and Ireland are going through
similar upheavals in their own country;

the curriculum I showed you is just for
England; so there is a lot to do.

And that means that you can actually
do something to help so, if you're in

the IT Sector specifically yourself, you
can be, you have specific things to give,

like you could start a co-club, run an
after-school programming club in schools;

you could go to your school and give a
talk or just be a role-model;

you could speak to your computing teachers
and act as a mentor for them; but even if

you're not an IT or computing specialist,
you could talk to your school about what

their response to the new curriculum is;
is it a fearful one or confident one; what

can we do to get them more support to make
it possible, there are a lot of schools

and so this is a boots on the ground job,
this is not a sort of air war, something

that can be solved centrally, all of us
have to help, so if you just, if we all

all sit around and wait for somebody else
to do it, nothing will happen, right.

There's a kind of fantastic opportunity
here. So, just let me finish by going back

to our children; what are we hoping to
gain from this? I hope that our children,

if we make a good job of establishing the
new computing curriculum in its breadth

from computer science through to ICT and
digital literacy, if we make a good job

of that, I think they will become more
engaged and curious and playful about the

digital technology and also about the
natural world that surrounds them.

I want them to become creator, creative
users of computers and there's nothing

more creative than writing programmes,
actually. There's these enormous artefacts

that people build out of pure imagination.
I want them to be informed and empowered

citizens who understand enough about the
technology that surrounds them, that they

can make informed choices about it. Again,
harking back to our previous talk, and I

do want them to have jobs too. I haven't
emphasised that very much but in the

modern knowledge economy, nothing equips
you better for a good job than having the

skills that I've spoken about. So, I think
we have a kind of once in a generation

opportunity to do something remarkable;
to make a qualitative improvement in the

kind of education we give to our children.

So there is everything to play for;
but it's not going to happen by magic.

It's going to happen because you help to
make it happen. Thank you. [applause]