When he was collecting cardboard boxes, Jasuel Rivera’s grandmother thought he was just making a mess. And like any Dominican matriarch she asked him about “ese reguero.” Jasuel, 12, tinkered with the boxes until eventually he was building robotic toys powered by things like syringes.

According to Zona5, Jasuel’s family is not able to buy him the toys he wants, so he took to the Internet and books to learn how to create his own. Now, he has 12, including a functional semi truck, trailer, and other equipment you might find at a construction site that are all made out of recycled materials. “I didn’t have money to buy one, but I saw one like this on the Internet, so I made my own,” he said. “I liked it, so I kept on doing it.”

He has been very influenced by mathematician Blaise Pascal’s law on fluid mechanics, which he can better explain than me. Pascal’s law led him to trying different liquids to power his toys. In the end, he said water was the best choice.