Euler Circle

What Euler Circle does

Euler Circle is a private mathematics education institute that delivers college-level mathematics courses to advanced high-school students. Founded by Simon Rubinstein-Salzedo (PhD, Stanford, 2012, algebraic number theory), the program operates in a hybrid format with online classes delivered via Zoom and in-person instruction in Palo Alto, California. The curriculum spans roughly 18 courses ranging from foundational sequences (Transition to Proofs, Fundamentals of Higher Mathematics, Mathematical Thinking) to advanced undergraduate-level offerings (Abstract Algebra, Ergodic Theory, Differential Geometry, Complex Analysis, Analytic Number Theory, p-adic Analysis, Cryptography, Markov Chains, Generating Functions), culminating in a mentored student research program that produces co-authored publications. Instruction is supported by approximately 100+ teaching assistants drawn from Stanford, MIT, UC Berkeley, and other research universities.

The business model is B2C tuition-based, with revenue generated from fall and summer class sessions. Euler Circle uses an application-based, rolling-admissions process rather than open enrollment. Curriculum has been codified into textbooks published through academic presses (Springer, World Scientific, AMS), creating a secondary content asset. The institute operates under the Kaleidoscope Circles umbrella, which also includes Curie Circle (physics) and Turing Circle (AI), suggesting a multi-subject expansion strategy. The company reports 14 employees and shows no evidence of venture capital or institutional funding, indicating a bootstrapped or founder-funded operation.

Name

Euler Circle

Legal name

Euler Circle

Website

https://eulercircle.com

Company type

Private

Operating status

Operating

Headcount range

11–50 employees

Short description

Euler Circle is a Palo Alto-based mathematics institute offering college-level courses to advanced high-school students via hybrid online and in-person instruction. It operates under the Kaleidoscope Circles umbrella and is founder-led by PhD mathematician Simon Rubinstein-Salzedo.

Ownership category

akta.pro rank

Product category

Mathematics Education

NAICS

Exam Preparation and Tutoring (611691)

SIC

Services-Educational Services (8200)

akta.pro primary industry

Math Circles & Mathematical Communities (EDAMAEAC)

akta.pro secondary industry

College-Level Core Subject Tutoring (Gen Ed: Math, Writing, Sciences, Humanities) (EDANAAAJ)

Keywords

• Advanced mathematics education
• College-level math classes
• High school enrichment programs
• Proof-based mathematics instruction
• Mathematics research mentoring

Headquarters

HQ city

Palo Alto

HQ country

United States

HQ region

North America

Offices1 record

Markets served

GTM type

B2C

Offering type

Services

Cost components

Personnel, Operations, Marketing or Sales, Technology or R&D

Revenue model

1. Class Registration/Tuition: Revenue is generated through tuition fees for college-level mathematics classes offered to high-school students. The program offers fall and summer class sessions with application-based admissions.

Go-to-market motion1 record

Distribution channels3 records

Marketing channels3 records

Core offering

Euler Circle offers college-level mathematics classes tailored for advanced high-school students who have exhausted their school's curriculum. Classes are taught by PhD-level instructors and cover proof-based mathematics including abstract algebra, real and complex analysis, number theory, topology, cryptography, formal verification in Lean, and mentored independent research with expository paper writing. Courses are delivered in hybrid online (Zoom) and in-person (Palo Alto) formats during fall and summer sessions.

Product overview

Euler Circle is a mathematics institute offering college-level mathematics classes for advanced high-school students through a platform-plus-modules architecture. The core offering consists of multiple class products across different difficulty levels: foundational courses (Mathematical Thinking, Mathematical Information, Transition to Proofs, Fundamentals of Higher Mathematics), advanced undergraduate-level courses (Generating Functions, Markov Chains, Ring Theory and Algebraic Geometry, Abstract Algebra, Ergodic Theory, Differential Geometry, Complex Analysis, Analytic Number Theory, p-adic Analysis, Cryptography, Mathematics in Lean), and intensive summer programs (Independent Research and Paper Writing). The company also operates a Student Research Program providing mentored research opportunities. Under the Kaleidoscope Circles umbrella, Euler Circle offers related programs in physics (Curie Circle) and AI (Turing Circle). Supplementary offerings include textbooks based on class curricula published through academic presses. Classes are delivered in hybrid in-person (Palo Alto) and online formats via Zoom.

Differentiator

Problem solved

Functional benefit

Brands

• Kaleidoscope Circles: Umbrella program under which Euler Circle operates as the mathematics branch. Also encompasses Curie Circle (physics) and Turing Circle (AI).

Products and services

• Fall Mathematics Classes College-level mathematics courses offered in the fall term (Sept–Dec) for advanced high-school students, covering topics such as mathematical information, mathematical thinking, transition to proofs, fundamentals of higher mathematics, and generating functions. Classes are delivered in hybrid in-person (Palo Alto) and online formats.
• Summer Mathematics Classes Intensive summer mathematics courses held online over 5-week sessions, including independent research and paper writing, mathematics in Lean (formal proof verification), and Markov chains.
• Independent Research and Paper Writing Advanced summer course where students select a mathematical topic to study in depth and write a detailed expository paper of approximately 20 pages, including instruction in LaTeX, BibTeX, Overleaf, and Beamer for mathematical writing and presentations.
• Mathematics in Lean Summer course teaching formal proof verification using the Lean4 proof assistant, where students learn to teach mathematics to a computer and collaborate on verifying mathematical theorems.
• Markov Chains Advanced course covering probabilistic models including absorbing and ergodic Markov chains, mixing times, coupling arguments, and linear algebra techniques for analyzing stochastic processes.
• Generating Functions Advanced course on using generating functions to analyze sequences and combinatorial problems, covering ordinary and exponential generating functions, Bell numbers, Catalan numbers, and analytic properties for determining coefficient growth rates.
• Fundamentals of Higher Mathematics Yearlong introductory sequence covering linear algebra, abstract algebra, point-set topology, and real analysis, designed as prerequisite material for advanced Euler Circle classes.
• Transition to Proofs Three-quarter sequence teaching students to transition from numerical problems to proof-based mathematics, covering number theory, combinatorics, and analysis while introducing proof techniques.
• Ring Theory and Algebraic Geometry Advanced course studying geometric objects such as curves from an algebraic perspective, covering varieties, rings, Pascal's Theorem, Bezout's Theorem, and modern algebraic geometry approaches.
• Abstract Algebra Core undergraduate-level course covering groups, rings, fields, symmetry, Galois theory, and applications to number theory including proofs of Fermat's Little Theorem and the impossibility of solving quintic equations by radicals.
• Ergodic Theory Advanced course on properties holding for typical real numbers, covering measure theory, normality, Khinchin's Theorem, and formalizing probability using measure theory.
• Differential Geometry Course using calculus to study geometry, focusing on curvature of curves and surfaces, Gauss's Theorema Egregium, the Gauss-Bonnet Theorem, and minimal surfaces.
• Complex Analysis Course on calculus with complex numbers covering the Cauchy Integral Formula, Liouville's Theorem, Picard's Theorem, and the Fundamental Theorem of Algebra.
• Analytic Number Theory Advanced course applying calculus to study integers, covering the prime number theorem, Dirichlet's Theorem on primes in arithmetic progression, Dirichlet characters, and L-functions.
• p-adic Analysis Advanced course on p-adic number systems and their applications to analysis, topology, number theory, and the Hasse-Minkowski Theorem.
• Cryptography Course on modern cryptographic systems including Diffie-Hellman and RSA cryptosystems, number-theoretic foundations, digital signatures, and zero-knowledge proofs.
• Mathematical Thinking Yearlong problem-based course helping students transition from algorithmic school problems to sophisticated mathematical exploration, covering topics from number theory to topology.
• Mathematical Information Yearlong course introducing how mathematical theory intersects with real-world applications, covering codes, data storage, error detection and correction, and classical and modern ciphers.
• Student Research Program Mentored research opportunities for advanced students who have demonstrated ability to work on challenging problems, including open problems closely related to class material, with publishable papers co-authored with founder Simon Rubinstein-Salzedo.
• Euler Circle Textbooks A series of textbooks published by Euler Circle instructors based on class curricula, including books on cryptography, algebraic topology, transition to proofs, and ergodic theory, published by Springer, World Scientific, and the American Mathematical Society.

Quantifiable outcome

• Students produce publishable research papers co-authored with founder Simon Rubinstein-Salzedo
• +1 more outcomes

Segments1 record

Ideal customer profiles1 record

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Partnerships

Three partnerships are on record, tiered core and minor.

• Kaleidoscope CirclescoreStrategic or Co-development PartnerEuler Circle is the mathematics branch of Kaleidoscope Circles, an umbrella program for advanced education. This is an internal organizational structure rather than an external partnership. Kaleidoscope Circles also includes Curie Circle (physics) and Turing Circle (AI).
• Stanford University Mathematics Camp (SUMaC)minorStrategic or Co-development PartnerFounder Simon Rubinstein-Salzedo serves as lecturer for Program II at SUMaC, teaching algebraic topology. This represents a professional affiliation and knowledge sharing between elite mathematics education programs.
• The Art of Problem SolvingminorStrategic or Co-development PartnerFounder Simon Rubinstein-Salzedo previously worked at The Art of Problem Solving, another mathematics education provider for advanced students. Historical professional connection rather than active partnership.

Scale indicators1 record

Recent moves6 records

Expansion highlights5 records

Direct peers

• MIT PRIMES: MIT PRIMES is a research mentorship program pairing high-school students with MIT researchers, including in mathematics. It overlaps with Euler Circle's student research program as a pathway for high-school students to produce original work.
• IDEA Math: IDEA Math runs enrichment programs and contests for mathematically gifted middle and high-school students. It is a direct competitor in the advanced math enrichment market with similar hybrid delivery formats.
• AwesomeMath: AwesomeMath provides online and in-person summer programs and year-round courses for mathematically talented students. It competes for the same advanced-high-school demographic with problem-solving and proof-based instruction.
• Art of Problem Solving: Founded by Richard Rusczyk, AoPS offers advanced math curriculum, online courses, and textbooks for mathematically gifted middle and high-school students. Founder Simon Rubinstein-Salzedo previously taught there, making it a direct competitor in the same student demographic.
• Program in Mathematics for Young Scientists (PROMYS): PROMYS is a Boston University summer program for high-school students exploring number theory and proof-based mathematics. It targets the same advanced high-school audience seeking college-level rigor outside standard curricula.
• Ross Mathematics Program: Ross is an Ohio State-based summer immersion program in number theory and abstract mathematics for gifted high-school students. It is a direct competitor in the proof-based math enrichment space.
• Stanford University Mathematics Camp (SUMaC): SUMaC is a residential summer program for high-achieving high-school students studying advanced mathematics at Stanford. Euler Circle's founder serves as a SUMaC lecturer, and the two programs compete for the same cohort of mathematically advanced students.

Others

• Kaleidoscope Circles: Kaleidoscope Circles is the umbrella organization under which Euler Circle operates, also encompassing Curie Circle (physics) and Turing Circle (AI). It is the parent ecosystem and platform through which Euler Circle's expansion plans will be executed.

Emerging players

• Brilliant: Brilliant offers interactive online courses in math, science, and computer science, including advanced problem-solving tracks. It overlaps with Euler Circle's student demographic at the more advanced end of self-directed math learning.

Broad incumbents

• Khan Academy: Khan Academy provides free, broad math instruction across K-12 and early college levels. While not directly competitive at the proof-based level, it is the dominant incumbent in online math education that Euler Circle students typically use alongside more rigorous programs.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat3 records

Key risks6 records

Key highlights6 records

Customer concentration

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Revenue estimate

Valuation estimate

Number of profiles

Profiles1 record

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Euler Circle