GONZALES - Book-loving Steffany Cheney, 11, sat at a newspaper- and plastic-covered table inside the library’s meeting room on Friday afternoon with about nine other teens, finishing up a project with Ascension Parish Library’s Youth Services Librarian Ben Bell.

“Ma’am,” Bell said, addressing Cheney, “do you want to come up and make some blood for your sister?”

Cheney nodded, adding, “I also need a bag for my snot.”

This week Bell took Grossology - the science of all things disgusting - to area branches of the library, where teen participants learned to make fake blood and fake mucus.

The batches of fake blood the scholars of yuck whipped up were surprisingly easy for how realistic the product turned out.

But they learned that gross isn’t always as easy as it looks. Fake mucus, it turned out, takes some finesse.

The consistency has to be right at several stages of the production process, Bell said, otherwise you’ll get anything from chunky goop to firm putty.

It took some experimentation to get the ooey, gooey, slimy but malleable perfect ball of snot.

Cheney finally perfected hers, holding the greenish-yellow colored goo made from glue, water, borax and food coloring at eye-level, and letting it ooze down into her mixing cup.

“Now, I want to you take it and throw it against that wall,” Bell said.

Cheney’s didn’t stick. No one could get their snot to stick to anything, but their hands.

As Cheney joined her mom after the class, and handed over the extra bag of fake blood - made of light corn syrup, dishwashing liquid, red food coloring and just a touch of green to create that black-red blood effect - to her little sister, Randi, 9, her mom’s eyes lit up.

“Oh! We can scare your dad when he gets home,” the sisters’ mom said.

In addition to summer programs like Grossology, Bell said, the Teen Summer Reading Program is still on, ending Sunday.

For more information on making your own gross recipes with common household items, visit http://grossology.org.