The idea is good. I think one of the most effective ways of getting kids to learn is by combining two key elements: (1) visual learning and (2) gaming. This is precisely what this idea proposes.
I don't believe the concept is truly original. However, originality does not matter to me as much because sometimes the best solutions are the simple, yet effective. This is definitely a simple, practical and effective idea.
My only issue is w.r.t scalability across communities for a couple of reason:
1. Only 10% of the world's population has access to Internet. Kids in developed countries might be tech savvy, but in the developing world the story is very different. Access is the first hurdle, followed by knowledge and time.
2. Different cuisines / cultures - For this application to succeed, it is absolutely essential that the game developer has a robust understanding of different cuisines, and creates localized modules for individual communities. In addition, cultural sensitivity will also be equally important.