When the national final of the prestigious Pythagoras Quest mathematics competition is held, no fewer than four schools from Internationella Engelska Skolan will be represented in the 14 teams involved.
To reach the final the young mathematicians were first given an hour to complete a qualification test, without a calculator or other electronic help. The best performing three students from each school were then selected to take part in a district finals, held throughout Sweden.
Now, following victory in their respective districts, IES Eskilstuna, Linköping, Karlstad and Uppsala will each be sending a team to compete against one another, and ten other schools from across the country, to see who will win the national contest this year.
As any of the students taking part could explain, that means a staggering 28.57 per cent of the mathematicians at the national final will come from IES schools.
Henrik Angelstig, who studies at IES Linköping in class 9B, won the Östergötlands final alongside Juliana Holmberg and Omor Almamun. He said: "The competition goes slightly beyond the school level and that is what makes it worthwhile to take part in, it is not your normal standard problems but lots of thinking outside the box ones.
"Many of them will be problems you have not encountered before, so you have to think of a really new solution that you have not practiced before. The way the question is formulated is not what you are used to from school.
"When you spend a lot of time thinking about a question or some part which you are not quite able to solve, you get a sense of achievement when you finally manage to crack it, that is a good feeling.
"I am very intrigued by mental challenges of any sort, from suduku to crosswords and playing chess. A maths competition is a good way to get to extend that hobby further, and you get to communicate with lots of other people who share the same interests, meet the other people with the same thoughts and principles as you."
Charlotta Eriksson from 9C at IES Karlstad was joined in the team which won the final for Värmland by Hanna Åkerstedt, also of 9C, and Anna Hulteberg, of 9A
"We felt surprised we would be going to the final because we didn't think it went really well.
"Our teacher, Mr Arvidsson, told us to enter and we knew it was a team competition and that made us want to. We are all in the same maths class and we know each other well. We all like maths and we think it is fun especially problem solving. This competition needed a lot of number skills and shortcuts, but mostly you can figure it out. Some knowledge is needed above the normal grade nine level, but what we always do in the lesson is above what we need to do. It is always nice to have more of a challenge."
Oskar Carlsson, from class 8F at Internationella Engelska Skolan Eskilstuna, competed as part of a team alongside Sofie Ohlsson of 9C and Gabriel Gilgren of 9E
He said: "This is the first time I have ever competed in a maths competition, it was very exciting, some problems were hard but then it was easy when I got into it.
"The bonus question seemed very hard, and at first we couldn't solve it, but in the end we found a solution. That was some algebra, and we were very happy that we found a solution, it was Sofie who did most of the work on that question.
"I think the final will be much harder and more difficult to do but we hope for the best.
"Maths is an important everyday life tool that you use to solve questions or measure the length of something or the area. I think about engineering for the future, so I will need to use maths."
15-year old Hugo Erixon, of class 9B at IES Uppsala competed alongside Rika Nakato from class 8D and Anja Zhou of class 9C.
He said: "Going to the regional final felt really weird, I didn't think we had that big a chance of winning. When we won it was a big surprise, but when I understood fully that we had won it was a pretty great feeling.
"Since then I looked at the website for the competition. It said the average points for all the teams was 21 or 22 and we have 26, so maybe we do have a chance for the final.
"I have always found maths really fun and challenging and enjoyable and I like to study a lot of maths. I am currently studying the first course of gymnasium maths, much of it is very similar to grade nine maths, with a bit extra on it and the problems step up a level.
"I like algebra and those areas the best, I find that geometry has a lot of rules and formula that you need to remember, and if you don't remember them it is hard to figure a problem out."
Damian Brunker, head of academics for Internationella Engelska Skolan, welcomed the results that the students have achieved. He said: "We are very proud of the high academic aspirations shown in our schools, and mathematics is one of the core subjects where our students perform far better than average when it comes to achieve top grades in the national tests.
"However, there is always room for improvement and competitions like this are inspirational; they help students to aim higher. This competition is just one of the ways that we can provide an extra challenge to students who excel at mathematics, encouraging them to reach further than they thought possible."
Now the winners of the regional events are preparing their skills, ready to travel to Skåne for the national final, which is set to be held in Malmö on Friday 27 May.