My student, Danny (age 6), and I were wondering if there are any animals other than the elephant and the walrus who have tusks.

Other animals with tusks include:

Warthogs

Some species of whales

Some deer

Other animals related to the elephant, like a wooly mammoth.

I'm sure there's more, but here are the ones I could find.

Then, of course, there is the Narwhal!

http://www.narwhal-whales.com/