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LEGO Ventures invest to bring Eedi to all schools and teachers

Craig Barton

I'm delighted to announce that Eedi (the parent company of Diagnostic Questions) has secured a significant investment from none other than LEGO Ventures. Let me tell you how this came about, and what it means for you.

The early days

I had the idea for Diagnostic Questions some 7 years ago when I was lucky enough to hear Dylan Wiliam speak in Bolton. That day he shared many effective ideas for improving formative assessment, but the one that stood out for me was the use of carefully designed multiple choice questions. These questions could be used to assess the understanding of all students (not the one or two that were on the receiving end of my previous questioning techniques). Moreover, students' choices of answers could give their teacher an insight into the precise nature of their misunderstandings, which was a huge advantage when deciding how best to help them. 

I left that talk buzzing, determined to build a platform where teachers could share these questions. The problem was my technological skills peak at control-C, control-V. So, I called up my friend Simon Woodhead, who I had collaborated on some textbooks for the dynamic graphing package, Autograph, several years before. 

Simon loves a challenge, and so for the next year most evenings and weekends were spent writing questions and code (and trying to convince our beloved partners that this was definitely a good idea). I also travelled the country, showcasing the pedagogy of asking and responding to Diagnosis Questions in class, and promising teachers that if they wrote me 5 questions, I'd give them 50.

Finally, in February 2014, we had enough questions and code to launch our creation:

In those early days, the website was very basic. I envisioned it as merely a community where teachers could share questions, and that's exactly what it was.

Data with destiny

A data with destiny

Our breakthrough came when we started to collect data. 

Simon built the functionality so students could answer each question by choosing A, B, C or D. Given the nature of Diagnostic Questions, where each answer is designed to reveal a specific misconception, this now meant that teachers using the site could learn not just which of their students got a question right or wrong, but start to understand why.

This led to some fascinating insights. I developed the game Guess the Misconception (it still amazes me that Ant and Dec have not snapped up the rights), which revealed that often the misconceptions we as teachers think are students have are not the ones they actually have. This has profound implications for all teachers, but particularly for novice teachers who do not have the bank of experience available to pre-empt the difficulties their students may have. 

But adding this functionality meant we also had to facilitate students having accounts, as well as design data analytics pages, classes, homework setting, and all sorts. Even something as seemingly minor as allowing a student to move class could cause the site (and Simon) to have a meltdown. 

Our little hobby was getting out of control. 1000s of teachers were using the site, but it was too much for Simon and I to manage. So, we looked for some help...

We needed money

Dragon’s Den

To get help, you need money. The problem was, neither Simon nor I had any business experience. Despite a degree in Economics (keep that quiet, please), my business experience was limited to running a semi-successful conker selling business at the age of 7. Simon had even less. 

And so, we turned to TES to see if they could help. I vividly remember showing Ann Mroz a single question, and the insights about misconceptions we could glean from it, and she loved it. And so did her boss. It came as a shock to me and Simon that TES were very interested. And no sooner had I asked the question, than Simon and I found ourselves dressed in suits, preparing a “deck” and pitching our idea to a US venture capitalist. And once again, much to our amazement, they were interested too, and all of a sudden we had money in the bank.

That enabled us to hire Gan Lu, a programmer, and Diana Padron a designer. And our little team of four set to work improving the website, fixing bugs, and building some of the many features teachers were asking us to. I was still teaching full time at this stage, and so I would come home at night, mark my books, and then try to catch up on the business side of things until the early hours. It was hard for everyone, not least my wife who essentially found herself single for a few years.

The problem was that the TES investment soon started to run out, and questions were asked as to how we planned to monetise. We toyed with a premium product that would offer extra insights, dallied with the idea of selling reports to parents, we even considered registering as a charity and trying to get by on donations. But none took off. Both Simon and I believed the core product should remain free. But we had the issues of salaries and hosting costs to pay.

So once again, we looked for help.

Ben Caulfield - CEO Eedi


Then Ben Caulfield came along – the newly appointed CEO of a tutor company. He saw a natural synergy with our product in that it could provide unique insights to tutors that would enable them to really understand the specific nature of the misconceptions their students’ held, thus making the support they gave more efficient.

Simon and I loved the idea. I mean, we were desperate, but we still loved it.

And so an acquisition was organised where Ben, Simon and I would be the co-founders of a new company, which eventually came to be known as Eedi.

The Eedi Team 👋

Another data with destiny

(Yes, I like that pun so much, I have found a way to use it twice…)

Pretty soon it became apparent that the tutor market was overcrowded, and that the strongest element we had at our disposal was our data. Without spending a penny on marketing, around 70% of UK secondary schools and 50% of UK primary schools were using the platform. That meant millions of data points about the specific nature of students’ misunderstandings about mathematics.

And so, Ben closed the tutor side of things and all attention was focussed on growing Diagnostic Questions and Eedi.

The dark days

But whilst everyone seemed to love what we were doing when I presented at teacher conferences and Ben talked to investors, we kept returning to the issue that we had no money coming in.

Again, we thought about premium offerings, donations and parent reports. But none seemed to work. We had managed to raise a few rounds of investment from a band of loyal investors (Dylan Wiliam and his partner Siobhan among them), but money was fast-running out.

They were the worst days for me and the rest of the team. Each month we didn’t know if we could make payroll. We had a large team working on a product we all loved, but we didn’t know how long it would last. Our team was so great. People went 3 months without salary because they wanted it to work so much. I was on a sabbatical from teaching at this stage so I could dedicate all my attention to Diagnostic Questions and Eedi, and so I was in the same boat as everyone else – trying to find money each month to pay the bills. Again, thanks must go to our partners throughout all of this for sticking with us.

During this time, the lone voice of optimism was Ben. He was the one who kept us going – essentially finding coins down the back of a metaphorical sofa to keep us going a few more months. Favours were called in, we applied for every research grant under the sun, our previous investors dug deep, and month after month we scraped by.

Aside from the uncertainty, the hardest part in all of this was the fear that all our efforts would be in vain. Not only could we not build the features that we wanted to build – and that teachers kept asking us to – there was a real possibility that one day the website would just disappear. Hosting with that many users and that much activity costs a fortune, and the coffers were bare.

LEGO Ventures!

And then one day, Ben assembled the team together over the phone as he had some news. Now, I am a natural cynic, so I approached the call with caution. We had had so many false starts over the last few years that I wasn't going to get my hopes up again.

But Ben said this was different. We had an investor lined up. Someone who believed in us. A big name. Someone who could really make a difference. And that investor was LEGO Ventures.

Over the next few months there were legal back and forths, documents to be checked, due diligence to be performed, and more than a few sleepless nights. But now we are in a position to announce the investment.

What does the investment mean to you?

Here are a few things the LEGO Ventures investment means:

1. Diagnostic Questions will remain free to teachers forever

This was always the most important thing for me, and Ben and Simon feel the same. As a teacher I have benefited so much from the generosity of others, and I wanted to give something back. I want a platform that any teacher can use to find out about their students’ understandings and help them accordingly, no matter what school they are from, what budget they have, and what trying circumstances they are working under. I have seen the power of these insights with my own students, and I don’t want anyone to miss out on that. A teacher will never have to pay a penny to use Diagnostic Questions, and that makes me so happy.

2. Diagnostic Questions and Eedi will get better

We can now start to build some of the features that we have wanted to for years and years. I am sworn to secrecy about the specific details, but let’s just say that we have ideas about how to solve many of the pain points that I felt as a teacher. We don’t just want to save teachers time, we want to enable them to do their job better.

3. We can engage in more research

Simon loves data. Unfortunately he has been tied up programming for much of the last 7 years. Now he is freed up to do what he loves. Those of you who follow my weekly emails will have already seen the fruits of his endeavours in the form of the research we conducted into the role confidence plays in understanding mathematics, particularly with the Hypercorrection Effect. We are currently working with Dr Colin Foster to turn this into a research paper.

But that is just the beginning. Our data enables us to look at how misconceptions change over time, find connections between them, track them across different countries, across different subjects, and much, much more. The potential for understanding how students learn is astounding.

4. We can grow to include more subjects

There are thousands of questions on Diagnostic Questions for subjects outside of mathematics. Computer Science, languages and the sciences are particularly well populated. But they don’t have the same coverage and structure as mathematics for the simple reason that I am pretty clueless outside my nice maths bubble. But now we can bring experts on to help, so every subject can benefit from the kind of insights that maths teachers enjoy. And how about some cross-curricular insights – what misconceptions in mathematics could cause problems in, say, Biology?

5. LEGO® Sets

This is the big one for me. I have received some awesome sets from LEGO Ventures which I have loved building with my little boy, Isaac.

Thank you

So, I am incredibly excited about the future. It has been a tough ride getting here, and a ride that very nearly came off the tracks a number of times. We couldn’t have done it without the help of the following:

• Dylan Wiliam – for giving me the idea and supporting  us over the years

• Our team – for sticking with us in the dark days, never giving up, and working so hard on a product that they believe in

• Our families – again for sticking with us through the highs and lows

• Ben – for never giving up

• Simon – for helping me realise my dream

• Our investors – for believing in our vision, for being patient, and for allowing us to keep going

• And finally… our users – you are the reason we do what we do. Whether you are a teacher, a student or a parent. We built this platform for you. And we are so excited about your reaction to what the future will bring.

Thank you, thank you, thank you


Written by
Craig Barton
Head of Education

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