Scuba diving is the only way left to find hidden treasure, befriend a nautical skeleton, or strap a huge tank to yourself. Explore the possibilities with today's Groupon: for $25, you get an introduction to Scuba class at Underwater World Scuba in Ralston (a $50 value).

The PADI-certified aquanauts, with more than 35 years experience, at Underwater World instruct future saltwater explorers in diving techniques during 90-minute classes at the Ralston High School pool. Strap on the provided materials, including an air tank and flippers, and bookmark key phrases in your Merfolk Translation Guide while learning the basics of safe diving and underwater breathing. Classes take place on the second and fourth Sunday of each month, excluding holidays, and full class information is obtained upon registration.