By day the Science Museum of Minnesota is awash with kids. But on some nights, it becomes a playground for adults — to drink, go on scavenger hunts, even sack out in sleeping bags beneath towering dinosaur skeletons.

The museum is among several Twin Cities attractions long geared toward children that are trying to broaden their appeal and add to their bottom line by offering more adults-only events.

The Science Museum has held two sold-out adult sleepovers since last fall, and the Minnesota Zoo plans to have its first adult sleepover later this year. The Minnesota Children’s Museum will hold an adults-only evening in its newly renovated 74,000-square-foot building later this year, giving grown-ups a chance to enjoy the new laser maze and catwalk.

Officials say such events help the zoo and museums add thousands of new visitors each year, many of whom have fond childhood memories of them.

“We know people need to play their whole lives. Play is not just for kids,” said Bob Ingrassia, the Children’s Museum vice president of external relations. “We are excited to have adults come in.”

Ingrassia said adults get the chance to tinker, explore and create in a low-stress setting where foibles and failures are a part of learning. “Many of the experiences will be fun for adults,” he said.

Sara Kerr, a spokeswoman for the Children’s Museum, said that while adult nights raise revenue, that’s not the primary point.

“It’s more mission-oriented,” Kerr said. “We really want everyone to be playing more. There is all this research that has come out about the benefits of play where you are doing something without a goal in mind. You are enjoying the process.

“CEOs value creativity and problem-solving in their employees. Those skills come from play.”

Under the dinosaurs

Even though half the Science Museum’s visitors are adults without children, it began hosting creative adults-only events in 2011, such as a murder mystery, bike night and a lights-out night. Those events attract between 1,000 and 2,000 people with a median age of 29. Tickets cost $18.95 with discounts for museum members.

“We theme them each time to keep it different and new,” said Kim Ramsden, a Science Museum spokeswoman. “By theming it, we are able to reach different audiences.”

At a recent 21-plus event at the Science Museum, adults with beers and cocktails drifted across the museum floor, checking out exhibits and chatting with staffers. Electronic club music played in the background.

Joey Pate, 22, of Minneapolis, who was examining an exhibit on the amount of blood in the human body, didn’t dance around the benefits of adults-only nights.

“I don’t like kids, but I like to come to the Science Museum,” Pate said.

The Science Museum, which has long hosted sleepovers for kids, experimented with an adults-only overnight in October. The event sold out, so it hosted a second one in April attended by 300 people who tucked their sleeping bags in and around the exhibits. One of the more popular spots to sleep is below the dinosaur skeletons.

Tickets cost $99 with discounts for members, and included two meals, a snack and drink, a late night Omnitheater show, make-and-take workshops and live demonstrations.

Will Joerger, a 26-year-old from Brainerd who works in technology, attended both of the museum sleepovers. The last time he had explored the place was when he was in fifth grade.

“It was fantastic. The staff was super friendly and were fun to hang out with,” Joerger said. “You have all these people in the same area and they enjoy a common interest — science.”

Joerger said he tackled the scavenger hunts and other activities with gusto. He connected with new acquaintances with whom he’s stayed in touch via social media. He said people from ages 21 to 70 were at the event, with most between 25 and 40.

He said he finally lay down to sleep about 3 a.m., when the staff turned down the lights.

“I get so excited I can’t sleep,” said Joerger, who was up at dawn for a yoga class offered as part of the event.

Joerger said he’s always been curious about how science works, but that he thought it was “kind of weird for a mid-20s guy to go to the Science Museum alone.” Nor did he want to be “that guy” spending 15 minutes at an exhibit with a line of kids stacking up behind him.

Reconnecting with the zoo

The Minnesota Zoo, which started hosting a monthly 18-plus night in 2015, is adding more dates this summer. Those events, which run from 6 to 9 p.m., draw between 1,500 and 3,000 and are often paired with the zoo’s world speaker series. Tickets for adult nights cost $10, though zoo members get in free.

This fall the zoo will host its first adult sleepover, including dinner, drinks, breakfast, activities and T-shirts. Adults will be able to camp among the shark tanks and sea life of the Discovery Bay exhibit.

Zoo spokesman Josh Le said adult events were added when zoo officials realized lots of folks went to the popular Music in the Zoo concerts without touring the exhibits.

“We want it to be a touch point for new adult visitors who have been disconnected with the zoo. They can reconnect with the zoo and our mission to save wildlife around the world,” Le said. “It’s a chance to get up close. They can see the animals without blocking kids or strollers in the way.”

Anna and Eric Johnston, of Apple Valley, have attended adult nights at the zoo and the Science Museum. In April, they met 10 friends at the Science Museum for an adult birthday party. The activities spice up what ordinarily would be a dinner-and-drinks night out.

It’s nice not to feel like your fun is coming at the expense of a child’s good time, they said.

“I felt like I can stay at an activity and play as long as I want,” Anna Johnston said.