Simply use attention and logic to sort all color balls by the different tubes
It is like chess but more interactive and a little bit simple that's good even for kids who don't know chess rules and strategies.
Place the selected ball to the ball of the same color in another tube, if there is free place. Main target is to sort all of the balls by color.
In every level you have a back button (but only 5 charges) so be careful and calculate actions by several steps ahead.
Also, if you get stuck it is possible to use a special + "additional tube" button.