The crossword puzzle was created as an accompanying material to discussions at schools on the topic of cyber security. Children aged 10 to 12 years have the task to solve it in groups and discuss the topics with the lecturer. We have also used this resource as a recommended material for parents during the "coronavirus holidays" to go through the concepts with their children and talk about Internet safety together. These are: Wi-Fi and its security; cyberbullying and how to fight it; the digital footprint and what it creates; rules for creating passwords; online games and communication among players; fake-news and information validation; on-line addiction.