This Popular Mechanics television series teaches kids about the science and technology that make the world a fun and interesting place. In these four episodes, hosts Jay, Elisha, Tyler, and Vanessa jump into creepy crawly sewers and piles of garbage in search of leeches, roaches, worms, and more!

Slither & Slime investigates the question all kids want to know, and makes it look like a grand adventure: Where does a toilet flush go exactly? Junior hosts Jay and Elisha conspire to find out, with the aid of New York City sewer personnel, by dropping green dye and a ping-pong ball down an ordinary toilet and watching these items progress through sewage and processing systems that ultimately release cleansed (if undrinkable) water back into natural destinations. But Slither & Slime is also about what else is below our feet: a glimpse at the giant water tunnel under construction 66 stories beneath New York (due for operation in 2025), the look of subway maintenance late at night, and how tunnel-boring machines ("moles") dug their way under the English Channel to create the British-French "Chunnel." Spectacular footage and wry humor make this a great way to see below the surface of things. --Tom Keogh