Entertainment-wise, daytimes are pretty much dominated by shore explorations. In addition to water sports (see below), the ship offers a variety of excursions in port, most of which are fairly standard sightseeing. Prices are in euros, which makes the excursions expensive if the euro is strong against the dollar or pound.
The sign-up process was pleasantly low key. At the beginning of the cruise, sign-up books for each island are set out in the library and guests can add their names to the lists at their leisure. If you change your mind, you simply cross your name off the list. You have until noon the day before to sign up or cancel (cancellations later than noon may incur a charge), but many of the tours did have last-minute availability. The cruise director is happy to answer any shore tour questions you may have, and does a presentation about the various options on one of the first nights. On the whole, the tours are well run and most of the group sizes are fairly small. But if you have your heart set on a particular tour, keep an eye on the bookings as tours can be cancelled if minimum numbers aren't met. This tend to happen more in the Med, where a lot of passengers are on their home turf and don't feel the need for sightseeing. In Cuba, there's more enthusiasm for exploring ashore.
The good news is, because the ship is so small, it gets into some of the nicest, and most 'yachtie' ports in the Mediterranean and you can just step off and stroll ashore in beautiful places like Portoferraio in Elba.
Daytime activities on sea days are pretty homespun. They're led by the cruise director and the water sports team (which also doubles as the activities staff), and include things like fruit carving demonstrations and knot-tying lessons. On the transatlantic crossings, passengers send messages in bottles, too, just for fun.
The most exciting daytime activity is climbing the mast, allowed on calm days, which involves putting on a rock-climbing harness, ascending a tall ladder, and hanging out in a crow's nest above the Sun Deck (the photo ops are better when there's land nearby).
On our Mediterranean cruise, Star Clippers was experimenting with a new wine buyer and there were excellent wine tastings on deck at 5:30 p.m. on three consecutive days; the buyer was friendly, knowledgeable and generous with his pours. There were also two cookery demonstrations from a Michelin-starred chef, but these were very basic. Some cruises also have a yoga theme, with an experienced instructor on board; check the Star Clippers' website for these as they happen just a few times a year.
Most people use sea days to sleep in the sun, read or take a dip in one of the two saltwater pools. Simply enjoying the sailing is entertainment in itself, watching the crew raise and lower the sails, maintain the rigging and steer the ship. There's an open bridge policy and passengers are often found chatting to the captain, or the officer of the watch.
Every evening at about 9:30 p.m., the cruise director hosts some kind of show, typically involving audience participation. Favorites include a fashion show of logowear, guest and crew talent show, team trivia and a hotly-contested music quiz. Sometimes, films are screened outside on the Aft Deck, projected onto an old sail; a very peaceful, very no-frills version of Princess Cruises' "Movies Under the Stars".
There's always dancing in the Tropical Bar, after the entertainment, to live music (typically, a keyboard player) or recorded music. The scene gets pretty lively as people stay up drinking with new friends and the jolly bar staff add to the atmosphere. The later hours are when several of the crewmembers -- officers, sports team -- come to hang out, so it's a nice opportunity for passengers and crew to intermingle. Star gazing is a perfect evening activity when weather permits, but though we even went up to the bridge to find a knowledgeable stargazer, most crewmembers were sadly lacking in constellation information.