The Nikon School is offering access to all their online classes for FREE (regularly $15 to $50 each) for a limited time. Classes are taught by professional photographers and range in topics from using Nikon products to in-depth lessons of learning the fundamentals of photography.
Olympus and Leica are also offering complimentary online sessions for a limited time. These sessions range from interviews with renowned photographers, virtual meet-ups, weekly photo challenges, and more. Space for these sessions is limited so participates can interact with the host and will require you to register the session.