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cipher-challenge.bsky.social
Harry
@cipher-challenge.bsky.social
150 followers 27 following 78 posts
Join Harry at the National Cipher Challenge, which invites school-aged participants to put their code-breaking skills to the test every Autumn. Created by the School of Mathematical Sciences @UniSouthampton.
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cipher-challenge.bsky.social
Harry @cipher-challenge.bsky.social · 15h
Over 5000 already registered at www.cipherchallenge.org ready for the practice challenges to start tomorrow at 3pm. If you are aged 11-18 and want to learn codebreaking and show the world what you can do then head over and sign up!
National Cipher Challenge
An annual codebreaking competition for UK schools and homeschooled students run by the School of Mathematical Sciences at the University of Southampton
www.cipherchallenge.org
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cipher-challenge.bsky.social
Harry @cipher-challenge.bsky.social · 8d
Love it! Would also love it if any musical cipher challenge aficionados out there feel like adding to our collection of themes!
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Harry @cipher-challenge.bsky.social · 16d
The 24th National Cipher Challenge is now open for registrations and we have already had 1200 sign ups. The competition starts on October 9th, so there is time to register your teams and get them investigating codes and ciphers. Catch up on our news at www.cipherchallenge.org.
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Harry @cipher-challenge.bsky.social · 20d
Day 1 and we have reached our first 500 registrations at www.cipherchallenge.org already! Will we beat last year's record 9,000? That is up to you!
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Harry @cipher-challenge.bsky.social · 21d
Ready to register for the National Cipher Challenge? The site opens tomorrow. Did you know that as a teacher you can monitor the teams at your school? You will be able to read more about that at www.cipherchallenge.org/how-to-bulk-...
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Harry @cipher-challenge.bsky.social · 23d
Just a few days now until the 2025 National Cipher Challenge opens for registration! If you know someone aged 11-18 who might like codes and ciphers (or who might not yet know that they do!) then get them to take a look at www.cipherchallenge.org on Thursday.
Registration opens 18th September 2025. Competition starts 9th October 2025.
www.cipherchallenge.org
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Harry @cipher-challenge.bsky.social · 26d
Tom, this looks great! Congratulations!
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Harry @cipher-challenge.bsky.social · 26d
We are looking for additional content to add to our Community page. You can read last year's at 2024.cipherchallenge.org/boss-your-ci...
If you took part and would like to feature on this year's site, then do get in touch either here or by email at [email protected]. We would love to hear from you!
Meet some of the Cipher Challenge community ... - National Cipher Challenge 2024
Your stories about taking part in the competition.
2024.cipherchallenge.org
cipher-challenge.bsky.social
Harry @cipher-challenge.bsky.social · Sep 8
Posters for this years www.cipherchallenge.org should be arriving in schools this week. If you want to help promote the competition, why not post a picture of the poster on your boards?
Registration opens 18th September 2025. Competition starts 9th October 2025.
www.cipherchallenge.org
cipher-challenge.bsky.social
Harry @cipher-challenge.bsky.social · Sep 2
Yes! Should arrive in schools for around 8th Sept!
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Harry @cipher-challenge.bsky.social · Sep 2
Holding a Clubs/Societies/Enrichment Fair for your school or college? The National Cipher Challenge might be just what you need. Here is a poster you can use to promote it! The site will open for registration on Sept 18th and the competition starts Oct 9th. Challenges weekly throughout term!
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Harry @cipher-challenge.bsky.social · Aug 26
Thank you! We will soft launch around 18th Sept for registration, with all the usual resources available then. Competition starts with the usual practice rounds from 9th Oct.
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Harry @cipher-challenge.bsky.social · Aug 26
Yes it is! Posters are stacked ready to go out, and the website is being updated. We really hope you like it!
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Harry @cipher-challenge.bsky.social · Aug 12
Want something to read on these idle summer days? You could take a look at this short article by one of our cipher challenge competitors: mathsrant.com/2025/07/28/t...
(Not that the Elves at CC HQ are idle. Far from it - too much to be done in prep for the new adventure. More soon!
The National Cipher Challenge – More Than Just Codebreaking
I’ve been meaning to write about how I got into codebreaking — so here’s the start of a small series on maths, ciphers, and curiosity. A lot of experiences have shaped the curious, questioning pers…
mathsrant.com
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cipher-challenge.bsky.social
Harry @cipher-challenge.bsky.social · Jan 14
It's true that you sometimes need to generalise a conjecture in order to prove it, but as a general principle I think "generalise then prove" (rather than "prove then generalise") is what Sir Humphrey might call "brave".
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Harry @cipher-challenge.bsky.social · Jan 11
Just a heads up that now the challenge is finished we are working on the leaderboards, prizes and invitations to the National Cipher Challenge event @bletchleypark. Please do keep an eye out for messages from us on the site, and log in regularly to see if we have left one for you in your account!
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Harry @cipher-challenge.bsky.social · Jan 9
Great! Will be very pleased to see you back!
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Harry @cipher-challenge.bsky.social · Jan 9
Sorry I didn't pick up on this before, it's a really important issue-also why time bands on the challenges are broad. Except the very last challenge any correct entry before 11pm on Friday gets maximum marks, so even if they don't meet til lunchtime Friday they still have every chance of success.
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Harry @cipher-challenge.bsky.social · Nov 14
PS, we are keen to hear about your experiences with the challenge, so do reply if you are happy to talk about it. And if you have any news that you would like us to share then reply or email us at [email protected] to let us know.
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Harry @cipher-challenge.bsky.social · Nov 14
We are well underway with the competition at www.cipherchallenge.org, though it is not too late to get involved if you fancy it. You'll be joining over 8500 other participants & there are still 6 challenges to break over the next few weeks. The next one goes live at 3pm today. Hope to see you there.
National Cipher Challenge
An annual codebreaking competition for UK schools and homeschooled students run by the School of Mathematical Sciences at the University of Southampton
www.cipherchallenge.org
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cipher-challenge.bsky.social
Harry @cipher-challenge.bsky.social · Nov 7
Over 8,000 signed up ready to take part in the competition at cipherchallenge.org this year! The first competition challenge runs until next Wednesday, so it is not too late to join in. Hope to see you there!
National Cipher Challenge
An annual codebreaking competition for UK schools and homeschooled students run by the School of Mathematical Sciences at the University of Southampton
cipherchallenge.org
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cipher-challenge.bsky.social
Harry @cipher-challenge.bsky.social · Oct 26
"In the past, I have made no secret of my disdain for Chef Gusteau's famous motto, "anyone can cook". But I realize only now do I truly understand what he meant. Not everyone can become a great artist, but a great artist can come from anywhere." Anton Ego, Ratatouille
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Harry @cipher-challenge.bsky.social · Oct 26
"How do I explain that!" is a pretty good definition of the substance of mathematics!
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Harry @cipher-challenge.bsky.social · Oct 26
Not sure I agree that angles don't appear in modern geometry.
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Harry @cipher-challenge.bsky.social · Oct 24
Excellent point about the factors. I like the thought experiment: if we met and talked to aliens about the geometry of circles would we be more surprised if they used degrees or radians?
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