The Pattern Keepers Mail Adventure
A year-long adventure story delivered by mail once a month, revealing a side of math that's filled with wonder, hidden patterns, and exciting discoveries. Available in the US only.
- For curious kids & families who want to nurture a lifelong appreciation for mathematics.
- For a memorable year-long gift filled with patterns, puzzles, and surprising discoveries.
Recommended For Ages 7-11.
Giving The Pattern Keepers as a gift? Download our printable welcome letter to give or send to the recipient.
The Pattern Keepers
The Pattern Keepers is a year-long mail adventure for ages 7–11, designed to spark curiosity, wonder, and a love of discovery.
Each month, a new letter arrives with the next chapter of an unfolding mystery, along with puzzles, games, activities, and other surprises inspired by fascinating patterns and mathematical ideas. Rather than feeling like another lesson or worksheet, The Pattern Keepers turns learning into an adventure kids can look forward to.
What if my child is younger or older than 7–11?
The age range is a guideline. Younger kids may enjoy it with some grown-up help, while older kids who enjoy puzzles and patterns may enjoy it too.
Does my child need to be good at math?
No. The story and activities focus on curiosity, patterns, and discovery rather than formulas or traditional worksheets.
Is this a math curriculum or tutoring program?
No. The Pattern Keepers complements classroom learning with surprising patterns, ideas, and connections kids may not encounter in school.
I would like to cancel. Can I get a refund?
Yes. Everything is a one-time purchase, so if you'd like to stop partway through, we'll refund you for any letters that haven't yet been sent. Here is the cancellation link.
What comes in each letter and when do they arrive?
Each mailing includes the next chapter, activities and puzzles, a note for grown-ups, and surprises like games, illusions, and more. Letters are mailed on the 15th of each month.
I’m giving The Pattern Keepers as a gift. Is there a welcome letter I can give the recipient?
Yes! Download our printable welcome letter.
How many letters are in the complete adventure?
The complete adventure unfolds across 12 chapters.
Do the letters tell one continuous story?
Yes. Nora and Calvin's mystery unfolds across all 12 chapters.
Will my child need help from an adult?
Some kids will be able to read and explore the letters independently, while some activities may be more fun or easier to complete with a little grown-up guidance.
What kinds of math will my child discover?
Topics include triangular numbers, prime numbers, partitions, palindromes, number patterns, magic tricks, symmetry, and other surprising ideas.
What is the Note for Curious Grown-Ups?
It explores interesting ideas connected to that month's discoveries and gives grown-ups the background to explore them with their child.
Can I find you on social media?
We share fascinating mathematical ideas in easy-to-understand short videos on TikTok and Instagram. Follow us @mathletters.
If I buy the First Letter, will I automatically be charged for the rest?
No. There's no automatic billing at all. The First Letter is a one-time purchase, and it comes with a QR code you can scan if you'd like to continue with the remaining 11 letters as a separate one-time purchase.
I moved. How can I change my address?
Email us at contact@mathletters.com with your old and new addresses, and we’ll update it for you.
I received the first-letter trial but lost the QR code. How can I order Letters 2–12?
No problem — you can order Letters 2–12 directly here.
Free Math Letters Book
I’ve gathered many of the mathematical ideas I find most fascinating into two books: Math Letters for adults and high school students, and Math Letters Jr. for younger readers.
Free Substack
A couple of times a month, I’ll dive deeper into fascinating ideas that deserve more than a short TikTok/Reel.
We also run a small design studio creating award-winning card games and giftable decks. Check it out if you’re looking for something fun to play or the perfect little gift.
About Us
Math Letters was created to explore a side of mathematics most people rarely get to see, filled with surprising patterns, fascinating ideas, and unexpected connections.
At the heart of Math Letters is The Pattern Keepers, a year-long mail adventure for kids and families. We created it with our own two boys in mind to nurture their curiosity, encourage them to notice patterns, and help them become confident, independent thinkers.
For adults and older kids, we’ve gathered many fascinating mathematical ideas and discoveries into the Math Letters and Math Letters Jr. books, both available to download for free.
We’re based in Chicago, Illinois. Zac has a background in mathematics and computer science, while Lana is a software engineer with a background in teaching and creative writing.
Contact
701 Main St. Evanston IL 60202