Thought : (About Cutting Game) Visibility Compare to the sample in the article, cutting game has relatively few function, and all the functions are mapping to controls one by one. This will not make user confused. For the tool (button), Scissor, pencil, eraser , hand, and the X(exit) are the most understandable tools But the effect of scissor is not realistic compared to cutting real paper with real scissor. The PageUP (arrow point upside), PageDown (arrow point to downside) buttons are not used by child at first, because they were originally been instructed to use the preview function to view multiple picture simultaneously. But in the recent days, I find that they learn to use them by themselves. I think it may be result from the simple function the button provi...