Postdoctoral Investigator Sarah Cooley (right), of the Marine Chemistry & Geochemistry department, leads a group of teachers through a classroom laboratory exercise exploring ocean acidification and its effects on marine organisms. The exercise was part of the December 2009, “Topics in Oceanography,” workshop held at the WHOI Ocean Science Exhibit Center. The containers hold liquids of different pH levels produced by various common substances, and an indicator that changes colors with changing pH. Workshops are given twice a year and are sponsored by Woods Hole Sea Grant, the WHOI Information Office, and the WHOI Academic Programs Office. The teachers are (left to right): Valerie Bell, Nauset Regional High School; Carolyn Sheild, Jonas Clarke Middle School, Lexington, MA; Christopher Ratley, Swampscott High School.