Whale season is between December and March in Maui. There are TONS of whales during whale season. Well technically only one whale would constitute a ton but you know what I mean. You can just see them from the beach. And if you have binoculars even better. Good places to watch whales are on a whale watching cruise, but also from the lookout point along the road to Lahaina just past Maalea harbor, and from the Kealia boardwalk at the bird pond. I took these from a Pacific Whale Foundation tour boat. Another great way to see whales is to go out with the Maui Canoe Club.