He might not seem like the most obvious heartthrob, but when Bill Nye enters the building, people shriek. That was the scene Sunday morning at BookPeople, where Nye — aka “Bill Nye the Science Guy” — spent an hour signing bookplates for his new book, “Everything All at Once,” which will be released in July.

Nye was friendly but efficient as he greeted each of the hundreds of fans who stood in a line that looped around the store and down the stairs. A documentary about Nye, called, appropriately, “Bill  Nye: Science Guy,” will show at SXSW tonight.

Robby Cole and his dad, Robert, dressed in matching blue shirts and bow ties for the occasion.

Robby Cole and his dad, Robert Cole, dressed in matching attire for the Bill Nye signing at BookPeople on Sunday morning. Kristin Finan/American-Statesman

Robert Cole said meeting Nye seemed like a great opportunity for his science-loving son.

“(Nye) has had such an impact on the world of science, not just by what he knows, but by what he inspires,” Robert Cole said.

Robby Cole agreed, adding, “He’s just so awesome.”

The audience included both children who are currently watching Bill Nye’s science programming at school and adults who said he influenced their career paths.

“He inspired me to study science,” said Nick Nguyen, who is doing just that now at the University of Texas.

Friends Cristina Cano-Calhoun, Nick Nguyen and Jennifer Perales at the Bill Nye signing at BookPeople. Kristin Finan/American-Statesman

Nye made a point to spend a little extra time with the children who came to see him, pointing out one little girl’s shirt, which read, “Yay science!” to the entire room.

Ruby Ragsdale, 7, said she’s learned a number of things from watching Nye, including that “your left lung is smaller than your right lung so your heart can fit.” She said she enjoys using her microscope and her science kit at home. Her current plan is to be a baker, but she’ll consider science, too.

Ruby Ragsdale shows off the bookplate that Bill Nye signed for her. Kristin Finan/American-Statesman

Her dad, Ian Ragsdale, said he and his wife wanted to bring Ruby to the signing to reinforce the idea that no career is off limits for her.

“We’re really big on making sure Ruby knows she can do anything,” he said.