For my kids (8 and 6) we started with "hour of code" from code.org. They especially liked the one with maze solving: https://studio.code.org/hoc/1 of course we tried others later.Then we tried some ScrachJr - they really like creating short clips with all family members as characters. ScratchJr makes it easy to use face photographs on animated characters. They could easily spend 3 hours doing just that which proves that they must really like it (it's hard for my 6 year old son to concentrate on one thing only for that long). Now we are trying a programmable robot from Lego Boost (set 17101). They like to play with it for sure but we have it only since Christmas so that's not that long.