Scratch - Scratch is the programming language & online community where young people create stories, games, & animations.
Tynker - Game Worlds for Kids to Learn Programming
GCompris - Educational Game for Children 2 to 10 years old.
RoboGarden - RoboGarden provides a complete, game-based suite that teaches coding from beginner to professional level, starting with block programming and progressing to professional Python and JavaScript programming.
Tux Paint - Tux Paint is a free, award-winning drawing program for children ages 3 to 12 (for example, preschool and K-6).
ScratchJr - Coding is the new literacy!