Brain Test Level 101 Answer
Handing out the apples one by one until the plate is bare and the level refuses to end. Three children and three apples looks like simple division, and it fails on the second half of the instruction.
The puzzle
Give them all apples, but never leave the plate empty.
The answer
Hand an apple to the first two kids, then give the third kid the plate with the last apple still on it.
What most people try first
Handing out the apples one by one until the plate is bare and the level refuses to end.
Why that is the answer
Three children and three apples looks like simple division, and it fails on the second half of the instruction. The plate has to keep something on it, so the last apple can never leave. Give the first two children an apple each, then hand the third child the plate with the final apple still sitting on it. The plate is a container, and handing it over is still giving.
If your level 101 looks different
Unico Studio shuffles level numbers between game versions and platforms, so the puzzle on your screen may carry a different number from the one here. If the question above is not the one you are looking at, the full levels 101 to 150 walkthrough lists every puzzle in this stretch by its question, which is easier to match than a number.