Nestled under the bridges of Interstate Hwy. 394 in the Minneapolis Lowry Hill neighborhood is Spring Lake. At first it's hard to see. Overgrown cattails, purple loosestrife and buckthorn hide the 25-foot-deep lake, which itself is too unhealthy to sustain fish or other wildlife.

But a science teacher at the Blake School has a plan for Spring Lake.

Dan Trockman's high school environmental science students will regularly test the water quality to determine why the lake is damaged.

Working with the neighborhood's association and the Minneapolis Park Board, Blake students also will continue to clear invasive species and plant young trees around the 12-acre park.

It is all part of an effort to emphasize environmental learning and community service at the school.

Around the region, environmental issues are coming to the forefront in some high school science classes. Though science teachers have taught these issues for years, more media attention, student awareness and state standards have prompted some educators to rethink how they teach about the environment.

Issues are global, not personal

Within the scientific community on a national level, there is discussion over whether recent weather changes are just cyclical occurrences or are actually because of global warming -- the term that has come to imply that human activities are warming the Earth's atmosphere, said Jean Tushie, a biology teacher at Eden Prairie High School and a National Science Teachers Association board member. But there does seem to be consensus that humans are at least contributing to the changes, she said.

In classrooms, most teachers recognize there are scientific and political disagreements over global warming and encourage their students to debate the issue. Science teachers -- who naturally point to data and scientific analysis to explain concepts -- usually leave their personal opinions out of the classroom, teachers said.

At Eden Prairie High School, increased media attention on environmental change has caused students to become more interested in acid rain and the concept of global warming, among other issues, Tushie said.

In the biology department, Tushie and her colleagues use a team approach to teaching.

"The seven of us talk about it and decide this is what we'll do so all kids gets the same experience," Tushie said. "You get the best of the collective group."

In biology, students study food webs to see how pesticides have disrupted the chain. They look at how early bird migration can upset the balance in nature. They also learn about local environmental concerns, including lake water quality and invasive plants.

At the Blake School, a semester-long elective course on the environment was added to an existing semester class that dealt with general environmental science. The new course will focus more on the effects people have on the environment through energy use, laws and other activities.

Both courses will be taught by Trockman, who received school grants to purchase the professional water-testing device for his classes' field-study work at Spring Lake. The additional elective was created because of student demand and the school's desire to address more environmental topics, said Rand Harrington, PK-12 science department chairman at Blake.

Sciences at all grade levels in the school are being evaluated to make sure classes reflect the school's mission statement and address current issues, he said.

"We have to be kind of visionary and think about the right tools to give [students]," Harrington said. "We have a tremendous responsibility to our planet."

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