Leave the summer camp s'mores and the short-sheeting of beds to the kids.
From fantasy sports camps with major league players to boot camps for aspiring astronauts, rockers, zombie slayers and world poker players, there are plenty of summertime options for adults seeking to cross big-ticket items off their bucket list or or just try something new.
Music fans can take lessons from rock stars who serve as counselors at the Rock 'n' Roll Fantasy Camp held in Las Vegas and, starting in October, at Foxwoods Resort Casino in Connecticut. Four-day packages begin at about $5,000 and include loaner instruments and lunches, but not lodging.
The hefty fee didn't deter 51-year-old Ron Cianciaruso, a musician and a senior vice president at a major bank in Jacksonville, Florida, from signing up for what will be his second session at Rock 'n' Roll Fantasy Camp: the upcoming four-day camp that will feature The Who's Roger Daltrey as one of the counselors.
"Yes, it's a lot of money," Cianciaruso told CNBC. "But it's a once-in-a-lifetime opportunity. And when you do anything like this as an adult you can appreciate the value in doing the things you love."
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Sports enthusiasts can hang out with their heroes at a wide variety of baseball and basketball fantasy camps, many with registration fees for adults hovering at around $5,000 as well.
Wish you could go into space?
The U.S. Space & Rocket Center in Huntsville, Alabama, offers a weekend-long Adult Space Academy for those who want to learn what it's like to train to be an astronaut. Campers get to hang out in one of the world's largest space aircraft collections, construct and launch rockets, and train on simulators, including the one-sixth gravity chair and Multi-Axis Trainer.
The three-day camp costs $549 per person while the four-day program runs $649. Meals and lodging are included.
For those worried about a zombie attack, weekend-long sessions at the Zombie Survival Course, held near Whiting, New Jersey, teach campers age 21 and older skills that might come in handy should there be a zombie apocalypse or some other disaster.
"It's very much a camp-like experience, but with crossbows, pistols and training in advanced first-aid techniques and hand-to-hand combat," said Zombie Survival Course founder Mark Scelza.
The $450 price includes lodging and meals.
"We're ready for zombies, hurricanes, earthquakes, even martial law now," said 34-year-old Ivory Mejia, an ultrasound technologist from Hull, Georgia, who took the course recently with her husband.
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"Adult camps often take place in traditional camp settings and can be the adult version of a kid's camp," said Peg Smith, CEO of the American Camp Association. And adult campers are likely to be baby boomers interested in "taking their vacations while supporting their vocations," she said.
According to the ACA, the 12,000 organized camps in the United States are part of a $15 billion industry, with 11 million children and youth and more than 1 million adults attending camp each year. The ACA's Find a Camp tool lists 200 adult camps, while its business affiliate GrownUpCamps.com has more than 800 paid listings for camps, courses and experiences.
Here are a few more options:
In Ely, Nevada, two of the three Railroad Reality Week summer sessions offered by the Nevada Northern Railway Museum are for adults only. The hands-on experience promises time spent maintaining 19th century locomotives and rail cars "with all the dirt and grime, you'd expect" and working as part of a railroad crew out on the track.
(Next session: August; price: $995; extra fees for bunkhouse lodging and "Be the Engineer" experiences.)
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World Poker Tournament Boot Camps in Las Vegas (of course) cover everything from basic poker instruction to tournaments and tells (betting patterns and physical behaviors). And the Culinary Institute of America offers two- to five-day-long boot camps ($895 to $2,195) on such topics as wine, pastry, grilling and barbecue at its three campuses in New York, California and Texas.
Many CIA campers are food and wine enthusiasts who want to learn in a professional kitchen with professional chefs, but the short sessions sometimes serve as gateways to something more serious. "We have had people attend Boot Camp, decide it was a life-changing event and then enter into the degree program," said Amy Townsend, CIA senior project manager for consumer marketing.
—By Harriet Baskas, special to CNBC.com. Baskas is the author of "Hidden Treasures: What Museums Can't or Won't Show You," and the Stuck at the Airport blog. Follow her on Twitter at @hbaskas. Follow Road Warrior at @CNBCtravel.