From the category archives:

Extra Credit

First Pics of Atomic Spin

by Sam Harrelson on April 28, 2010

Iceberg Physics (and Extra Credit)

by Sam Harrelson on February 27, 2010

Pressure Test Results (and Extra Credit)

by Sam Harrelson on February 15, 2010

Extra Credit: What To Do About Dihydrogen Monoxide?

by Sam Harrelson on January 31, 2010