I begin this lesson by showing this video about erosion. I start many lessons with a video in order to engage and hook my students in the lesson right away. The video also serves as a preview of what the day's topic of learning is. I chose this video because it uses the word erosion and gives examples of what erosion is. I want my students to be able to know this definition.
My students often sing with song videos, although I don't require it.
Erosion is not a new concept for most of my students. Many of my students spend time outdoors hiking and camping and are well aware of erosion. Since my state has thousands of acres of public lands and forests, many of my students have families that use these public lands often. Taking care of these lands and preventing erosion is already part of many of my student's background knowledge. To begin this part of the lesson, I ask students to write in their science notebooks about what they think erosion is.
You can listen to this student talk about what he thinks erosion is as he begins to write in his notebook.
I show this quick Bill Nye video clip to ensure that all student's are operating from the same definition of what erosion is.
After the video, I explain that they will explore erosion further by taking part in a hands-on activity. I lead a brief discussion about what students know about erosion and then ask students to think about a central question. The central question I pose is this: “What can be used on the hillside to slow or stop the soil from eroding? Can it be stopped?
Next, I show students a pile of dirt (about a gallon) in a large piece of tin pan (or do this outside with a mound of dirt and a hose with a spray nozzle). I then place little figures like plastic people, tiny houses, model trees, etc., in different places around the mound of dirt. Use a spray bottle or hose to spray the mound until the dirt starts to erode. Watch the people, houses, and trees slide down the mound.
You can hear at the end of the video, I ask students to raise their hands and explain what happened. I listen as students explain in their own words what happened to the figures and the soil as the water was poured on the dirt hill. I use the word erosion as students explain what they saw.
Next, students work in groups of 4 to create their own dirt hill and place figures on it. One person in the group pours water on the hill and group members watch and discuss what happens to the dirt.
As groups create their dirt hill, I circulate around the room and assist as necessary. I remind students about the central question after they pour water on their hill. I ask students to talk in their group about what they could do to prevent the soil erosion. This is an important question because students will have an opportunity in the next lesson to design a plan to slow erosion on their hill.
I direct students to turn and talk to their learning partner and talk about two things they learned today either from watching the erosion experiment or the video.
Next, I end the lesson with this song about erosion. This song elaborates about the differences between erosion and weathering. Students often sing along with the song.