Hi Robert, Thank you for your advice. I have just been to the supermarket and google some related products. They are in similar look but the colors are different. But, anyway your advice is quite crucial for the inventors and possible manufacturers as consumers will very likely to confuse them.
It's a significant idea that parents are the best teachers for their children. But I wonder it might be too costly to teach the parents. These parents might not have basic knowledge background and it might be hard for them accept new things. Instead, I think it may be good to teach the parents about the importance of education for their children.