A PS to Dab -- we've been happy to give you detailed advice from our experience, on the logistics of a Greece visit... how to reach a destination, where to stay, how to get around. But I hope this does not deter you from doing some real "homework" to greatly enhance your experience. I don't mean just the eating & sport activity -- I'm talking about the culture, the ancient sites, the stunning landmarks, the museum treasures... and one cannot get it all by flipping thru links on your computer or phone. There's nothing like a good guidebook --- and you have plenty of time to go to the library and bring home an armful. Go thru them, photocopy a few pages, then buy the one that speaks to you the most. If you're spending $10K on this Big Trip, it's worth 10-15 bucks for a guide. No need to buy the v. latest edition -- because you already use these forums & internet sites to get the most up-to-date info on hotels & transit ... and the info on culture, history, ancient sites etc, doesn't change that much. And here's an idea: Assign each of your teens a destination (I suggest Nafplio & Naxos) and challenge them to come up with a must-see, must-do list & say why!
Here are some worthwhile Guide options:
• RICK STEVES GUIDE -- Terrific on Athens -- PLUS this website has FREE downloadable audio step-by-step guides to Acropolis, Ancient Agora, the Natl. Arch. Museum -- & same info is also in print, in his guide. THIS enables u to D-I-Y your landmarks instead if in a huge tour. Good on Nafplio & surrounding area... For the Islands, look at other sources. SUPER-useful - his "Survival Phrase List" ... not for conversations (most Greeks speak at least some English), but to express yourself a bit, greet & thank people, etc. Many guides have such lists but his list shows clearly how to pronounce and (vital) what syllables to STRESS. Print out a copy for each family member to carry, and you'll be surprised how many successful connections you'll enjoy!
• ROUGH GUIDE -- I like this for indepth historical sites, maps, background, understanding of culture ... older editions again, are better than new ones, which overload on photos & travel directions. Ditto on LONELY PLANET. If any of your party wants a "deep dive" into ancient sites, the Blue Guides are the "Gold Standard."
On the internet, very worthwhile info sources are:
VISIT NAFPLIO -- http://www.visitnafplio.com/ NONcommercial, absolutely Gold -- don't miss links on Walks (like the water-edge one around the Peninsula point) and beaches/swims (my fave, Kastraki-Assine cove, plus the "plunge" just past the point)
GREEK FOOD & DRINK - https://www.greecetravel.com/greek-food/index.html - a great! illustrated compendium of Yummm