Unit 3 Guide
Unit 3 Guide
2Unit 3: LifeLiving organisms have evolved into billions of different species since life first emerged over 3 billion years ago. While the complexity of life has increased over time, many species are extinct, which tells us life on Earth is also fragile.
Unit 3 Learning Objectives1.Describe the origins of life on Earth. 2.Explain the differences between life and nonlife. 3.Describe how life on Earth changed over time. 4.Use evidence to explain adaptation and evolution.5.Evaluate how extinction events change life on Earth.For individual lesson learning objectives, please review the lesson teaching guides.
Big Questions In this unit, students will consider this Driving Question: Why did life begin on Earth, and how did it change over time?
Lessons Overview Lesson 3.1: Complexity of Life on Earth: How did complexity increase as life on Earth emerged?Lesson 3.2: Origins of Life: How did life on Earth begin and change?Lesson 3.3: Evolution: How did the evolution of life on Earth increase complexity?Lesson 3.4: Extinction Events: How do extinction events change the complexity of life on Earth?Follow the links above to explore each lesson in this unit. Look for this symbol to findthe lesson guides, which provide teacher guidance, including sample answers.
6Teaching Tips
Openers and ClosersYou’ll find quick opener activities at the start of each lesson. They’ll help students preview the upcoming material and engage their prior knowledge. Although we’ve written them to align with the content of each lesson, feel free to swap in any openers/do-nows/bell-ringers that you already use! You’ll find closer activities at the end of all lessons—they’re meant to give students the opportunity to reflect and show their understanding. While we’ve written them to align with the content of each lesson, feel free to swap in exit tickets or other checks for understanding. For more information, check out Openers and Closers Quick Tips.
Unit NotebookUnit Notebooks are found throughout this course and offer a great opportunity for informal writing and assessing understanding. The aim of these activities is to keep students and teachers connected to the core themes of the unit. The first time students encounter the Unit Notebook (Unit 3 Notebook: Part 1), they’ll be asked to evaluate each of the statements based on what they currently know. The second time they encounter the Unit Notebook (Unit 3 Notebook: Part 2), they’ll be asked to more thoroughly respond to the questions and revise and refine their initial understanding of the unit’s core concepts. The emphasis here is for students to focus on concepts rather than formal writing. Additionally, the Unit Notebook helps both you and your students assess how their thinking is progressing, where they’re gaining mastery, and where they might need additional instruction.Click here for the Unit 3 Notebook: Part 1.Click here for the Unit 3 Notebook: Part 2.
Thresholds of Increasing ComplexityUnit 3 focuses on the fifth threshold of increasing complexity: Life on Earth. Students will learn about the ingredients and Goldilocks Conditions that came together to create life on Earth. Each threshold is presented in a short video with an accompanying Threshold Card activity. We encourage you to have students complete each Threshold Card to help them remember how one threshold builds upon the next. By the end of the course, they’ll have a Threshold Card for each of Big History’s eight thresholds, which will help them in Unit 7, where they’ll determine what the next threshold might be.
ReadingsBig History includes articles written by a diverse group of scholars. Some of the reading involved in OER Project courses can be challenging, but it’s vital for engaging with the course content. All texts in the course—other than those that are part of DBQs (document-based questions) or are primary source materials—have been Lexile leveled, and each article has three or four versions to accommodate students of all reading abilities. OER Project provides Guiding Questions alongside each reading. These questions encourage students to approach the text at three levels—first by skimming the text, next by reading to answer Key Idea questions (“While You Read”), and finally by evaluating the text through “After You Read” questions that encourage connection and synthesis. For more information, see our Reading Guide.
Geographic and Historical Thinking SkillsThe integration of skills and content is foundational to OER Project courses. Skills development is just as important—if not more—than content knowledge for student thinking and learning in social studies classes. Throughout this course, students encounter numerous, scaffolded opportunities to practice causation and making and testing claims. Practice progressions are made up of two categories: progression activities and thinking tools. Each step in a progression is more sophisticated than the one before, challenging students along the way but also supporting them as they do this work. Learn more in our Historical Thinking Guide. In Unit 3, students evaluate claims about life on Earth in the activity Claim Testing: Life. They’ll also assess the causes of extinction events in the activity Causation: Extinction Events. Students explore geographic topics such as biomes and climographsand the impact of plate tectonics on life.
ActivitiesActivities are an important part of OER Project lessons and serve to build student understanding and engagement. Activities provide an opportunity to get students moving and “doing” history through exercises like informal writing, group work, simulations, and debates.Progression activities appear in multiple units and are based on geographic and historical thinking skills like claim testing and causation. Each activity in a progression is meant to be more sophisticated than the one before, challenging students but also supporting them as they do this work.For all activities in OER Project—except for some openers and closers—teachers can find directions and sample answers in the accompanying lesson guides. Click here to learn more about activities.Click here to learn more about historical thinking skills.
VideosWe use videos as a visually engaging approach to course material. While students are often excited to learn that they’ll be watching a video in class, video-watching is a skill, just like reading an article. Here are a couple of quick strategies to get you started:•We suggest students first read the video description and Guiding Questions, or even skim the video transcript. We’ve provided you with timestamps and sample answers, which students will not see. •We recommend chunking the videos using the Key Ideas feature, which pauses the video at the specific times of the corresponding Guiding Questions and provides an opportunity for discussion or note-taking.•You can also play the video twice: once straight through and once with pauses at key ideas.For more information, see our Video Guide.
Graphic BiographiesOER Project’s graphic biographies are one-page histories of people. Whether they’re “important” or “everyday,” each of these individuals has their own story, their own history, and those stories weave in and out of the global themes of their era. Their experiences highlight—and sometimes bring into question—developments on a global scale that students are studying as part of the Big History narrative. These biographies are one of the best ways for students to practice their scale-switching skills by zooming in, which helps bring nuance to their understanding of history. Click here to learn more about our Graphic Biographies.
WritingIn Big History, we want students to become comfortable with writing, which is why we offer multiple opportunities for them to write informally. Having students write informally allows them to gain comfort with writing as they think about concepts and what they’ve learned, rather than explicitly focus on formal writing techniques. Throughout the course, we ask students to practice writing. Sometimes students will be writing claims while in other instances, they’ll be writing a few sentences in response to the lesson Driving Question. The point is to provide lots of writing opportunities so that over time they become more comfortable with it. Click here to learn more about our writing approach.Click here for informal writing routines.