Personally, I’m a fan of telling creationists that if they think they have the information to overturn most of biology, they need to be telling the biologists, not me. But this is pretty good too. :) Give it a look see if you want to be ready to in depth with them.
Sci-Am put out a list of 15 rebuttals to creationists arguments.
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When not defending the planet from inevitable apocalypse at the rotting hands of the undead, JT is a writer and public speaker about atheism, gay rights, and more. He spent two and a half years with the Secular Student Alliance as their first high school organizer. During that time he built the SSA’s high school program and oversaw the development of groups nationwide. JT is also the co-founder of the popular Skepticon conference and served as the events lead organizer during its first three years.