An invention called “Mahlapump” deserves to be highlighted for the following reasons.
The author of this invention, Tõnis Reitalu, is not even at the school stage where these physical phenomena or solutions would have been introduced in the school's physics class. That means the inventor has an excellent self-learning ability!
Given that the author of the invention is only in 3rd grade, it can be concluded that this young man is curious, with good attention to the surroundings and natural technical intelligence, which are some of the main prerequisites for a successful inventor!