Teaching Public-Key Cryptography in School

These clays, public-key cryptography is indispensable to ensure both confidentiality and authenticity in numerous applications which comprise securely communicating via mobile phone or email or digitally signing documents. For all public-key systems, such as RSA, mathematically challenging and technically involved methods are employed which are often above the level of secondary school students as they employ deep results from algebra. Following an approach suggested in 2003 by Tim Bell et al. in Computers and Education, volume 40, number 3, we deal with the question of how to teach young students the main concepts, issues, and solutions of public-key systems without being forced to also teach rather complicated theorems of number theory beforehand.