Grade 7Science

Focus: In this unit, students investigate the phenomenon of changes to an ecosystem. They ask question about how one change in an ecosystem can affect many aspects within it. The subtitle of this unit is Does changing an ecosystem change what lives there? Students have familiarity from their own surroundings and from news around the world how changes to natural systems can affect, and even threaten the extinction of, organisms. Starting with an examination of how the world’s demand for palm oil threatens the ecosystem that supports the orangutan, students build an understanding of the interconnectedness of living things in an area. Students ask questions and explore other ecosystems to see how affect certain populations that are a part of the system. Then students confront changes in areas around them and make choices of how to communicate threats to the environment to others. This unit allows students to observe the phenomenon of a force acting through a distance in detail and then spend time working with classmates to analyze the shared experience, formulate new questions, and developing new strategies for answering them. Students explore concepts that include the following:

  • How could buying candy affect orangutan populations in the wild?
  • Can we grow oil palm trees somewhere else so that we’re not cutting down tropical rainforests?
  • How have changes in our community affected what lives here??
  • Would planting more rainforest fruit trees help the orangutan population increase??
  • What would happen if orangutans go extinct?
  • How does an ecosystem change when the plants change?
  • How can people benefit from growing food in ways that support plants and animals in the natural ecosystem?

As students move through their day-to-day activities, they will also read Core Knowledge literacy selections. These include factual articles, history of the sciences, art and literature, spotting bad science in the media and advertisements, graphics comprehension, research-type articles, reliability of sources, and other areas of science literacy.

Lesson Numbers:

  • Teacher Guide: 20 Lessons
  • Student Reader: 5 Collections

Lesson time:

  • Lesson can be competed in one or more class periods.
  • A Pacing Guide, found in Online Resources, offers the suggestion that the entire unit should take about 40 days to complete if class is held each day.
  • A complete list of materials needed to complete the unit is also provided in the Online Resources.
  • The Core Knowledge Student Reader includes one reading collection per week for every week of the unit. A week’s reading collection relates to the lessons completed in the previous week.
    • The reading is assigned at the beginning of the week with the accompanying writing exercise due at the end of the week.
    • The reading and writing exercises are designed to be completed by students independently, with brief, supporting, teacher-facilitated discussions at the beginning, midpoint, and end of the week.

Additional Search Terms for the Student Reader:

• science literacy • ecosystem • ecosystem dynamics • ecotourism • resource • ecology • habitat • habitat fragmentation • invasive species • population • population sampling • quadrant • transect • bottleneck effect • K-selection species • R-selection species • extinction • bycatch • monocrop • nonfiction • informational text


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