If you're considering teaching this book, you should read this thoughtful and helpful summary and review of Armstrong's Shipwreck at the Bottom of the World. If you're not familiar with the book, this review will help you know whether or not it's right for your class. FYI, in my experience, it's a winner.
I found this teaching unit on Teachers Pay Teachers for $9.95. If I were currently teaching this book, I would consider this unit worth the price. It includes many activities and links the Shackleton voyage to current events such as the Chilean miners’ ordeal in 2010.
You can buy the book on Amazon by following this link to its page. Their grade level recommendations begin at grade 3. I think this is a little too advanced for average third-grade readers. It might be better for fourth or fifth graders.
I found it impossible to choose just one resource, lesson, or section of this website. It is extremely slick and well-designed, with tons of information on Antarctica, including online activities for your students. There are so many possibilities for research assignments here.
How could anyone not love this? "Shortly before midnight a gale sprang up suddenly from the Northeast with rain and sleet showers." "I had three young and one old albatross for lunch." It’s the Shackleton voyage, in tweets! Don't miss the photos and videos.