Codebusters

Division: Div C – High School

Event Rules: See the National Rule Manual

National Event Page: Here

Description:

Teams will cryptanalyze and decode encrypted messages using cryptanalysis techniques for historical and modern advanced ciphers. 

Materials:

Teams must bring writing utensils and may bring up to three stand alone non graphing non programmable non scientific 4 function or 5 function calculators.  No resource materials may be used.  The Event Leader will provide scratch paper and will include a resource sheet with the Morse Code Table, English/Spanish letter frequencies, Porta Table, and Baconian mappings and modulus inverse tables as needed for the questions on the exam.

Scoring:

High score wins.

Recommendations:

This event allows up to 3 team members.  Teams are allowed to divide and conquer the test.

Event Resources:

User guide for Codebusters – 45 pages of resources!
Online Interactive tests instructional video
Codebusters 2019 Coaches Clinic Presentation (2018 Rules)
Codebusters Test Tools
The State event supervisor for Codebusters has set up a twitter handle to send out tips and tricks.  @NCSO_cb
Important update from the Coaches institute.  The K2 alphabet hint is actually a K1 alphabet hint.  Everything described works the same, just the label is a K1 instead of K2.  You can read on how to solve with a K1 alphabet at http://toebes.com/Ciphers/Solving%20a%20K1%20Alphabet.htm.
Previous tests can be found at http://toebes.com/Ciphers/index.html
Cryptoclub
CIA – break the code
The Imitation Game
Cryptograms.org
Test Builder Demo

Make your own codes:

Media:
The STEM Yard podcast featuring an interview and Q&A with Event Leader John Toebes.