Here is a “memory” game for children.
Find two equal pictures and the will be shown.
A list of buttons (important: Buttons must be created one after the other, so they get an increasing number from 1 to 20), a list of 20 images (10 pairs of equal).
First the list of images gets shuffled.
Then we react to a click of a button. Here we show the image of the button number in the imagelist.
We increase a counter to see whether it is the second guess. If both last tries are equal pictures let them be shown. Else reset the counter and show the question marks again.