Theodore Tugboat is essentially Thomas the Tank Engine on water, replacing the trains with boats. Nowadays it seems kids are watching stronger stuff than they used to in the past, and I feel kind of sad because of that - they're ruining their innocent minds and imaginations.
Theodore Tugboat is not like most modern kids' shows, however. Through storytelling by the late, great Denny Doherty (of The Mamas & The Papas fame), the titular tugboat and his friends in the Big Harbour learn some important life lessons and valuable skills such as teamwork, making friends and being good to each other. Kids will love to watch Theodore's wonderful adventures in the water, as will some adults who may remember listening to The Mamas & The Papas back in the day.
The show may now just be classic Canadian children's TV (it stopped at season 5, and there was never a sixth season), but Theodore lives on in his home of Halifax, Nova Scotia in Canada (where the show was filmed), where people of all ages ride him across the harbour every day - a tribute to his lasting legacy on the last two or so generations.