Details: With more than 25 hours of scientific lectures available on each cruise, you're bound to come home from these learning vacations with a brain brimming with thought-provoking information. Lectures are provided by Ph.D.s who are leading authorities in their fields and include such topics as human evolution, neuroscience, astronomy, conservation and even extra-terrestrials. Cruise rates start at $1,299 per person for an interior cabin; the seminar is an additional $1,475 to 1,575.
The Dates: February, June, September and November 2013 departures
Details: Following in his famous father Jacques' footsteps, Jean-Michel Cousteau has become a well-respected oceanographer, educator and filmmaker in his own right. He'll join four Paul Gauguin Cruises departures in French Polynesia in 2013, giving lectures and narrated video presentations. He'll also accompany divers on reef explorations. Cruises range from 11 to 14 days. Fares start from $4,995 per person (including free roundtrip air from Los Angeles).
Details: Thrill seekers rejoice. In March 2014, Crystal Cruises will be taking passengers aboard Crystal Serenity on a 21-night adventure through some of the world's most fascinating temples and safaris. The cruise will begin in Singapore and end in Cape Town, making stops in Thailand, Cambodia, Indonesia, Mauritius and South Africa along the way. Award-winning broadcast journalist Ken Rees and a number of special interest lecturers and enrichment instructors will be onboard, while available guided tours and shore excursions -- including a scenic Catamaran Sail & River Bank Lunch in Mauritius and endangered species tracking throughout South Africa -- can be enjoyed off the ship. Fares start at $8,220 for an oceanview cabin, although book-now discounts are currently available.