Lesson 4 of 8
Objective: SWBAT define a watershed (including stream system and tributary) and examine the factors that affect infiltration and runoff | SWBAT examine stream features including deltas, floodplains, levees, and meanders, including how streams change shape over time due to differences in deposition and erosion
In this lesson, students get a real-life glimpse into the creation of stream features using one of my favorite Earth Science tools: The Stream Table! But first, students learn a little bit about watersheds and how streams are fed through the process of infiltration and runoff. Then, we use a stream table (see below for a link to a cheap one) to model some of those very processes. We finish off the lesson with (of course!) some Regents-based practice to give students the chance to cement the cool knowledge they learned thus far. As a note, there are a few materials listed below, which you can substitute or find better options at your leisure (although my stream table was pretty inexpensive). Additionally, I wanted to provide students the adequate time with the stream table to model and see the developing features, so I did this over two days, despite the fact that it is solely presented as one lesson here.
- Stream Table (link to mine here - as a note, there are expensive models (and really expensive models) out there, although other teachers have found even cheaper options from hardware stores or the local Home Depot) (photos of my setup are here:Stream Table Setup I & Stream Table Setup II)
- Stream Table Sand (I don't see what's wrong with normal playground sand, which is a cheaper option. Living in NYC, I was constrained a bit by not having a vehicle, although if I did, I would have just went to the local store and picked some up.) [Note: This product, as well as general sand bags are heavy. Plan accordingly when buying and transporting]
- Waste Bucket (at least 5 gallons)
- Source of water (I use my sink) or large container capable of pumping water into the stream table. This pump works pretty well.
- Optional (but fun and informative): Plastic houses (like from Monopoly) (or army men - something that can stand up in the sand). Small blocks of wood or objects that can float in water
- Student whiteboards & markers: I use this to check their drawn meanders when they first learn about them to ensure that they're able to identify them and where erosion and deposition happen alongside them
[Note: For embedded comments, checks for understanding (CFUs), and key additional information on transitions and key parts of the lesson not necessarily included in the below narrative, please go to the comments in the following document: 7.7 - Stream Features (Entire Lesson w/comments). Additionally, if you would like all of the resources together in a PDF document, that can be accessed as a complete resource here: 7.7 - Stream Features (Entire Lesson)[PDF]. Finally, students may need their Earth Science Reference Tables [ESRT] for parts of the lesson (a document used widely in the New York State Earth Science Regents course) as well.]
Students come in silently and complete the (attached) Do Now. In this case, the Do Now is a review of material and some "hot standards" from earlier in the weathering and erosion portions of the unit. After time expires (anywhere from 2-4 minutes depending on the type of Do Now and number of questions), we collectively go over the responses (usually involving a series of cold calls and/or volunteers), before I call on a student and ask them to read the objective out loud to start the lesson.
As a general note, the Do Now serves a few purposes:
- It serves as a general review of the previous day's material;
- It is a re-activation of student knowledge to get them back into "student mode" and get them thinking about science after transitioning from another content area or alternate class;
- as a strategy for reviewing material students have struggled with (for example, using this as a focused review for material that they have struggled with on unit assessments or recent quizzes); and,
- It is an efficient and established routine for entering the classroom that is repeated each day with fidelity (I never let students enter the classroom talking. While it may seem potentially severe to have students enter silently each day, this is both a school wide expectation and a key component of my classroom. In many respects, I find that students readily enjoy the focus that starting with a quiet classrooms brings each day).
Drainage Basin & Watersheds
Post Do Now, we start the lesson by introducing the topic of Drainage Basins & Watersheds. We start with a group reading, which quickly defines a stream system and watershed. Students read together with their partners and answer the embedded questions on the first two pages of the Drainage Basins & Watersheds resource. Some of this information serves as a proto-review of material that has been previously covered in the unit, but most of this information is directly related to information on stream movement and the amount of runoff in stream systems. After approximately five (5) minutes, we return to a whole class discussion, where I call on select students and groups to provide their answers. We then utilize this information on runoff and watersheds in our next section, where we identify some major stream features and model the process of steam flow using a stream table.
The next section has two resources. The first part of the resource is done at their seats, and directly involves identifying major surface features carved out by moving streams. These include V-shaped valleys, floodplains, deltas, levees, and meanders. While this is vocabulary-intensive, the Stream Features resource provides some visuals, and many students are already coming in with the visual recognition that these stream features create. However, even absent that context, they're still going to be able to see these features be created in real-time with a stream table, so the features will become live for them as soon as they have that experiential anchor to latch on to later on in the lesson. This section, in effect, is to visually introduce and define these features. The text also expounds upon how these features are often created by moving water. For example, deltas are created by the slowing velocity of water, which causes a layered sorting of sediment buildup at the mouth of rivers, where elevation (gradient) is usually at its lowest.
Students are given about 7-8 minutes to work collaboratively on the section on Stream Features, making sure to define all the terms as they encounter them in the resource. While they're doing this, I would circulate to ensure fidelity to the task and accuracy of their responses (I would make sure all setup is done prior to students entering the room. Due to the space, heavy lifting, and large amount of water required for this, setting this up beforehand is ideal).
As soon as time is up, we, similar to the last section, collectively review the material as a class. [Important Note: This might be a natural breaking point if you're considering breaking up the lesson into two days, as this is where the preparation for the actual stream table demonstration really begins]. We then transition into the Meanders resource, where I begin with a short text defining meanders.
After we're finished with the stream features, we begin the section on Meanders by reading the text on the first page of the resource, which is quickly followed by the following animation. After reading the text and the animation, we very quickly define a meander (on the next part of the resource) before moving over to my stream table setup in the back of the room (some images here: Stream Table I & Stream Table II). I use a faucet setup to control the flow of water, but traditionally, a pump (link in Lesson Introduction) is more often used. Either way, water flow from one end to the other, where the wastewater is drained by plastic tubing into a bucket. The stream table is slightly elevated (and you can change this to show the increased erosion that results from the increased stream velocity) to facilitate the flow of water as well. What we do when I turn on the water is watch for the development of many of these stream features. If you turn the water on a relatively high pressure (it also helps if you start to "dig" out some channels for the stream), you can see the erosion taking place in real time - the meanders literally change before your eyes. A cool thing I've done is place some standing action figures/army men/Monopoly houses on the banks of the meander, which serve as visual anchors for when they either fall in the stream or get slowly buried by more sand (depending on their location). I think this is a relatively simple, fun, and super visual way to have students see the process of what's going on.
The Practice section in this lesson is, like the vast majority of questions found in all of my classwork and homework, is 100% Regents-based. All of the questions come from prior Regents examinations. Likewise, as I try to generally do with all of my lessons, the questions are mostly organized to get increasingly more difficult and increase in complexity, which is why the harder questions tend to come toward the end. For whatever reason, the Regents loves to ask questions about source regions and air masses, so I truly think the practice is worthwhile, considering this is something they'll see over and over and over again in the future.
In terms of student work habits, I tend to sometimes make this decision in the moment, and as a response of what I know about the students and how they're processing the material on, but I'll either ask them to work independently, in partners, or (sometimes) give them the option. Usually, before starting practice, we tend to go over some steps for self-help ("What should you do if you're stuck?"), and I might reference a previously used multiple-choice or free response strategy in order to build their skills while simultaneously learning content (as an example - one popular one we always use - "If you aren't sure what the right answer is, see if you can eliminate some wrong answer choices"). I tend to circulate for compliance and then hone in on specific students while they're doing this.
After about 10 minutes, we go over their responses. Students who finish early are encouraged to work on the exit ticket (resource below) and double-check their responses. We use a combination of strategies (active voting, cold calling, popsicle sticks, volunteers) to go over the responses, where students correct their work and ask any clarifying questions.
In the last few minutes of class, I have students complete the daily Exit Ticket. For the sake of time, I have students grade them communally, with a key emphasis on particular questions and items that hit on the key ideas of the lesson (Note: This usually manifests as students self-grading, or having students do a "trade and grade" with their table partners). After students grade their exit tickets, they usually pass them in (so that I can analyze them) and track their exit ticket scores on a unit Exit Ticket Tracker.
After students take a few seconds to track their scores, we usually wrap up in a similar way. I give students time to pack up their belongings, and I end the class at the objective, which is posted on the whiteboard, and ask students two questions:
- Do you feel that you mastered the objective for the day?
- Can you reiterate one thing you learned about (in this case, watersheds or stream features, etc.)?
Once I take 2-3 individual responses (sometimes I'll ask for a binary "thumbs up/thumbs down" or something similar), I have students leave once the bell rings.