Here is our weekly digest of free topics. Check them out now before they expire by the end of the week. In addition to these, up to 20% of our library is free on any given day. Log in to enjoy. Preparing for the Expedition Lewis and Jefferson wanted the expedition to start as soon as possible. But there was a lot to do first. Lewis began buying supplies. What Is An Endangered Species? Elephants. Tigers. Gorillas. Pandas. Blue Whales. What do these fantastic creatures have in common? They are some of the biggest, freshest, and most loved animals on the planet. They are all also endangered species. The United States…