About the Course

Cryptology: Cracking Codes

Unlock the world of secret communication in this engaging, fast-paced introduction to cryptology. Over six weeks, during live weekly sessions with your classmates and instructor, we’ll explore how mathematics serves as the foundation for encryption and decryption techniques. Designed to be approachable yet challenging, this course offers an accessible glimpse into the history and principles behind secret codes and ciphers, with a focus on real-world applications. We will uncover the logic, patterns, and problem-solving strategies that drive cryptographic systems, and deepen our understanding of how cryptology has developed throughout history to shape our modern encryption systems and secure our digital world.

Time commitment: 2.5-3.5 hours per week (1.5 hours of class time, 1-2 hours of independent work). Course will include 6 sessions over 6 weeks.

Course Overview

About Advanced Enrichment Courses

These courses offer above-grade-level material presented in a novel context, explored with other advanced learners, and guided by a CTY educator and help prepare students for higher-order thinking and college-style academic challenges.

The content in Cryptology: Cracking Codes overlaps with the CTY course Cryptology: Math and Codes. Students who have already taken Cryptology: Math and Codes may wish to consult with an enrollment advisor before selecting this course.

This course is

ungraded.

Classes

Register for an Online course by selecting an open class below. If no open classes are listed, then course enrollment is currently closed. Note: You will need to have an active CTY Account to complete registration through MyCTY.

Tuesdays
-
5 weeks
Tuesdays, 6:00 p.m. (ET)
$1,365
Enroll

Testing and Prerequisites

  Math Verbal
Required Level CTY-Level Not required
Check your eligibility using existing test scores If you do not have existing test scores:

Students must achieve qualifying scores on an advanced assessment to be eligible for CTY programs. If you don’t have qualifying scores, you have several different testing options. We’ll help you find the right option for your situation.

Sign up for Testing Learn More

Cost and Financial Aid

  • Tuition
    • Varies
  • Application fee
    • Nonrefundable Application Fee - $15 (Waived for financial aid applicants)
    • Nonrefundable International Fee - $20 (outside US only)

CTY Financial Aid Availability for Online Programs

Academic Year 2025-26 (Course start dates July 1, 2025- June 30, 2026): Financial Aid funding is currently available for all eligible students while funding lasts. If interested in applying for financial aid, please select a course with start date of July 1, 2025, or later.

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Course Materials

Please acquire all course materials by the course start date, unless noted as perishable. Items marked as “perishable” should not be acquired until the student needs them in the course. If you have questions about these materials or difficulty locating them, please contact [email protected].
 

Families will be notified by email of any required materials one week prior to the course start date.

Technical Requirements

This course requires a computer with high-speed Internet access and an up-to-date web browser such as Chrome or Firefox. You must be able to communicate with the instructor via email. Visit the Technical Requirements and Support page for more details.

About Mathematics at CTY

Our online Mathematics courses—spanning elementary through college-level curricula—cover a wide range of topics, from algebra and geometry to chess, cryptology, and AP Calculus and are guided by expert instructors. You’ll join group sessions with classmates to ensure you stay on track with challenging course content. Whether you’re looking for pure math fun and enrichment, to move up the math ladder and advance your honors and AP (and beyond) academic standing, or to train for mathematics competitions, there’s a CTY course that’s right for you.

New math enrichment courses available!

Explore our new math enrichment courses, including Excursions in Pre-algebra and Introduction to Logic and Proofs.

Join the exciting world of competitive math

Participate in the High School Math Club or enroll in 6 IP courses: Middle School Competitive Math I, Middle School Competitive Math II, Middle School Competitive Math III, Competitive Mathematics Prep, Competitive Mathematics I, Competitive Mathematics II.

Meet our Mathematics Instructors