The Digestive System
Lesson 3 of 7
Objective: SWBAT identify the structures of the digestive system and their functions.
As students enter the room, they take out their journals and respond to the prompt: What is the function of the digestive system? Explain.
Prior to this class, the students took notes on this topic, so I expect them to be able to provide a brief, accurate description. While the students write, I circulate through the room to review their responses.
During this time, I may ask them to elaborate on an idea, or further explain information. This is especially helpful in determining each student's level of understanding. This practice is also helpful in determining which portions of the information to emphasize and further explain as we review the notes.
For example, if very few students are using the terms chemical or mechanical digestion, I make sure that I review and explain the terms during the next portion of the lesson. Finally, checking in with the students helps them feel more comfortable with their answers, making them much more willing to share their journals with the class later.
I ask the students to keep their journals out for reference and I return the notes and Digestive System Notes Review that the students completed prior to this class period using their flipped digestive system flipped notes. I also open the Digestive System Presentation.
I then ask for volunteers to share their journals with the class, advancing the slides as necessary to review the information shared by the students. I also ask the rest of the class to provide additional examples or information based on the comments of their peers. In this manner, we are able to review the notes without me standing in front of the class and reading the notes to them.
In order to ensure that all of the information is accurately and adequately covered, I ask the students questions. For instance, tying back to the journal example of chemical and mechanical digestion, I ask the students to explain the two types of digestion in addition to explaining how and where they occur. I also spend time discussing how the digestive system impacts and is impacted by other body systems, such as the circulatory system. This review of the notes addresses NGSS MS-LS1-3 (The body is a system of interacting subsystems) as we discuss the structures of the digestive system and the ways in which the digestive system interacts with other body systems, as is listed as a question on the student notes review.
After reviewing the information from the notes, I have the students take out their Chromebooks and open the Digestive System worksheet. I open each of the websites that the students will be using for the activity and explain how each of the websites functions as we review the worksheet directions as a class.
I emphasize to students that the primary objective of the day's activities is to explore various models of the digestive system and then to critically examine the models in light of what we know about the digestive system to determine the accuracy of the models. This examination of the websites as models addresses NGSS SP2 - Developing and using models. The Cross Cutting Concept of Systems and System Models - Models are limited in that they only represent certain aspects of the system in study - is addressed as the students critically examine the models they use. Furthermore, the Cross Cutting Concept of Structure and Function - Complex structures and systems can be modeled to describe how function depends on the relationship between various parts - is addressed as the students use the models and see how food passes through each of the structures of the digestive system.
In the first activity, A Journey Through the Digestive System, the students take the form of a sandwich as they travel through the digestive system to meet various objectives on each level. I remind the students that for this activity I want them to specifically explore how the interactive matches what they know about the digestive system. This can be a difficult game, so I do not require the students to complete all of the levels, but the more levels they complete, the better able they will be to answer the questions.
The second activity, the Digestion Tutorial, focuses on the structures of the digestive system and their placement within the body. I remind the students to keep an eye out for how this is a model of the digestive system. The third activity, from E-Learning for Kids, provides students with additional information about the structures of the digestive system and their functions. After reviewing the information, the students take a quiz on the website to demonstrate their understanding of the topic.
The students complete the tasks individually and turn in their own copy of the assignment, but I do allow them to work collaboratively in terms of asking each other for feedback or advice in regards to how to complete an activity or item. While the students work on the activities, I circulate through the classroom to help the students troubleshoot activities, if necessary, and ask them to explain the models they are using.
At the end of class, I call the whole group back together in order to discuss the aspects of the online games as models of the digestive system. I ask students to look back at the information they had written about the first online game.
Many of the students recognize that one inaccurate aspect of the game is that the sandwich is never digested. I ask the students to explain what the sandwich might look like as it moved through the mouth and then to explain what it would look like as it moved into and out of the stomach.
Some of the students are quick to point out that the first activity is missing an esophagus, so I ask them if an esophagus is important and to describe what it does. I also ask the students to explain the model of the stomach in the first activity and to describe the type of digestion that was portrayed (chemical) and to explain how mechanical digestion might have been incorporated into the model. We continue in this manner until we have reviewed a majority of the aspects of the first website and then we move on to the second and third websites, as time allows. By doing this, the students are reviewing information about structure and function as well as exploring models.