Epsilon and Delta
Discovering the beauty of mathematics with elementary school children.
Level 1 Books
The Largest Number
Meet Epsilon and Delta, learn about sets and help Epsilon and Delta find the largest number.
Pairs of Cherries
Where did Epsilon and Delta get their names? Learn about prime numbers and see how Epsilon and Delta count a huge pile of cherries.
How to Build a Castle
Venn diagrams: mammals, four-legged animals and four-legged mammals. A castle with right angles. Two special functions: minimum and maximum.
How Big Is a Sheet of Paper?
How do we describe how big a sheet of paper is? A simple idea called Distribution. Watch out for union and intersection.
The Square of a Number
What is the square of a number? Multiplying with parentheses. Some new functions.
Sailboats
How large is the sail on a sailboat? More about variables. Venn Diagrams: are mammals a subset of animals or animals a subset of mammals?
The Main Idea
Epsilon and Delta is a series of mathematics workbooks for elementary school children. The books expose children to mathematics (and some computer science) that does not require much previous mathematical knowledge but that is nevertheless generally taught much later in their education. Sets, prime numbers and functions are good examples.
The books have two characters: Epsilon and Delta. The characters have discussions, such as if there is a largest number, and have adventures, such as building towers out of blocks and figuring out how many blocks they need. Each book has a special topic, story and several sets of exercises. The content is cumulative.
For Children
Level 1 is roughly intended for children in second grade. Level 2 will be written for the 2023-2024 school year and is intended roughly for third graders. Children will hopefully enjoy the books, experience the beauty of mathematics and develop an interest in learning more.
For Parents
Parents do not need to have any math experience to work with their children on the books. Each workbook will likely take 1-2 hours for a child to work through, ideally spread over several days within a month. It will certainly be helpful if a parent works with the child on the workbooks and discusses the work with the child. The books are not necessarily intended to help children with the mathematics they learn at school or prepare them for tests.
Families may subscribe to receive paper books mailed monthly at roughly the cost of printing and mailing or may download the books here for free.
Paper Delivery by Mail
We started with 15 children in the fall of 2022. Printing costs are about $3.00 per book and postage is $2.16 in the US. We ask parents to pay for the cost of the books and to help spread the word.
The books, however, will also be freely available online to download and print at home.
Sign Up!
The fee to sign up for mail delivery in the U.S. is about the cost to print and ship the books: $60.00 for ten issues per year (September to June). To sign up, please fill out the form below.