The Junior Mental Calculation World Championship returned to Bielefeld, 21–23 September, as organized by Caroline Merkel since 2008 [official JMCWC website]. 84 competitors from Algeria, Bulgaria, Canada, the Czech Republic, Germany, Hungary, India, Japan, Kyrgyzstan, Mexico, Qatar, Serbia, South Africa and the UAE qualified and attended—some for their first time, while others have attended for many years.
2024 was the highest-scoring year ever. Although this is a “junior” competition, several of the participants have won medals in international competitions open to adults—such as the MSO online and the MCWC 2024.
[Note: this information should be correct, but if you notice anything that needs correcting, please let me know 😊]
Under-12s age category
The youngest age category—”Junior 1″—was won by Mohamed Iyed M’Ghozzi, who achieved 3rd place last year, and was one of many Algerians with great scores this September! The maximum mark available was 2547 points.
- 1st: 🇩🇿 Mohamed Iyed M’Ghozzi (2225)
- 2nd: 🇩🇿 Douidi Wissal Firdaousse (2176)
- 3rd: 🇮🇳 Niva Vishal Gada (2049)
Many other participants showed their potential at a young age, and will also do well in future competitions!
Under-15s age category
The “Junior 2” category was the largest category this year, including many strong and determined mental calculators—32 entrants in total.
Kaloyan won his age category for the third consecutive year—with less than 100 points unclaimed on the entire paper! Last year’s gold medallist from Juniors 1—Andrej—is now 12 years old and competed very successfully in this older age group. Swanand improved his score by about 400 points to claim his first JMCWC medal. The maximum score was 2762.
- 1st: 🇧🇬 Kaloyan Geshev (2664 points)
- 2nd: 🇷🇸 Andrej Živanović (2550 points)
- 3rd: 🇮🇳 Swanand Bhore (2350 points)
Several other competitors made this category very competitive with scores over 2000 points: 🇩🇿 Manar Benmastora (2205); 🇩🇿 Anwar Ayat Arahmen Khelif (2148); 🇩🇿 Nouha Bouzidi (2110); 🇮🇳 Achyuttam (2095) and 🇮🇳 Veer Sahas Bagi (2094).
Under-20s age category
The “Senior” category had a maximum score of 2866 and was won again by Abhilakshya, who did not make any mistake or omission in the first 8 of the 30 pages. Radhika wins her fourth medal at the JMCWC with her highest-ever score. Walid, 🇯🇵 Mako Inokawa and 🇨🇿 Adam Šorf each improved their scores by over 500 points compared to last year, with Walid winning his first medal.
- 1st: 🇮🇳 Abhilakshya Arora (2730)
- 2nd: 🇩🇿 Walid Ksentini (2580)
- 3rd: 🇮🇳 Radhika Maheshwari (2515)
The Seniors category was a meeting of many experienced and impressive mental calculators. The following obtained scores above 2200 points and had potential to win a medal: 🇿🇦 Stiaan Scheepers (2436); 🇮🇳 Parth Garg (2366); 🇮🇳 Mishti Shah (2362) and 🇮🇳 Asmita Pal (2339).
Invitational age 20+ category
A few past competitors of the JMCWC who were helping at the event (after preparing for the MCWC) also took the Seniors paper for fun without necessarily preparing, and the highest score was from 🇩🇪 Joshua Spring (1774).
Congratulations to all participants who attended the event—and thank you for contributing to make these days a positive and enjoyable experience.
Format of the Championship
The main contest is a 2-hour paper that includes a variety of mental math categories, such as:
- 726446 + 294855 [1021301]
- Find the integer that squares to 15100996 [3886]
- On what day of the week was 28-Mar-1764 [Wednesday]
Here are some resources that may help students (and their teachers) to prepare for the championship.
The day before the competition, there were workshops for all the participants, provided by mental calculation experts:
- Daniel Timms (me—author of this website)
- George Lane (creator of the Pegasus mental calculation trainer, and 5-time gold medallist at the MSO)
- Elke Kuge
- Willem Bouman
- Martin Drees
- Freddis Reyes
- Johanna van Koningsveld
- Joshua Spring
- Walid Henni
The weekend was also very social, where both the children and their accompanying adults could meet others from around the world, for dinners, workshops and even a trip to a cake factory!
Hectoc Competition:
The Spring family organized a Hectoc competition, where participants had to produce the number 100 from a string of six digits (1–9) using the standard Hectoc rules. For example:
123456: 100 = 1 + (2 + 3 + 4) × (5 + 6)
224459: 100 = –2 + (2 × 44) + 5 + 9
There were 114 participants in total. Each participant’s score is the number of Hectocs solved correctly in 15 minutes, from a selection of 80 questions.
Contestants up to the age of 18:
- 1st: 🇧🇬 Daniel Dimitrov (52)
- 2nd: 🇧🇬 Kaloyan Geshev (51)
- 3rd: 🇮🇳 Abhilakshya Arora (46)
Contestants aged over 18:
- 1st: 🇩🇪 Joshua Spring (46)
- 2nd: 🇩🇪 Elke Kuge (34)
- 3rd: 🇩🇪 Martin Drees (33)
Some hectocs are more difficult to solve than others. 🇧🇬 Georgi Georgiev also attempted the Hectoc challenge, solving an impressive 63 of them!
Sponsorship for the JMCWC was generously provided by the Andreas Mohn Foundation.
Get Involved Next Year
Would you be interested in competing in this event, or do you know a young person talented in Mathematics or mental calculation? Here are some ways you can get started:
- This page has information about the 2024 paper (which was similar to the previous years’ papers)
- Try some of the medium-difficulty techniques, such as multiplication, fractions and exact cube roots of 6-digit numbers. With practice, your speed can improve dramatically!
- Contact Caroline Merkel (she organizes this event) for any communication about registering. This includes collaboration with regional events.
- Contact me (or other trainers) for any questions about training mental calculation.
- Look out for updates about future competitions. The provisional date for next year’s competition is 06 October 2025. Official confirmation and full details will be provided later by the JMCWC organizers when the details are ready. I hope to see you there 😊
It would be great to see even more countries joining next time!