Students identify the three realms of the Arctic Ocean, and describe the relationships between these realms. They graphically analyze data on sea ice cover in the Arctic Ocean, and recognize a trend in these data.

Learners explain the concept of paleoclimatological proxies. In this oxygen isotope lesson, students interpret data and make inferences about climate changes in the geologic past.

Students examine the role of signal corps during the Civil War and explore the technique of 'wigwag.' In this Civil War lesson, students discuss the way they communicate long distance today, they research how a civil war soldier...