Sunday, April 7, 2019

Build STEM Enthusiasm with a Microscope Center

Spring is a fantastic time to add a microscope center to your classroom. For students in grades 3-8,
microscopes are a gateway to science: awesome, amazing, and irresistible.

Spring brings vernal pools, which are home to a great diversity of small creatures. These tiny animals can be spotted with the naked eye, but come into greater focus with the microscope.

You don't need to be an expert in microscopy to help students discover amazing tiny creatures. (I'm certainly no expert!) All you need are microscopes, a safe place to put them, and the flexibility to let kids explore.

What You'll Need

In my classroom, I use a counter area for my microscope center. If you are using microscopes that plug in, you will want to make sure that you have safe access to an outlet with no dangling cords. (Trust me: Kids will trip over any cords that you leave lying about!)

Brock Magiscopes, if you can find them, are the best tool for informal classroom investigations. They focus easily and are quite rugged, making them perfect for younger students. Magiscopes don't need an outlet, either, although a nearby light source improves images. You can see in the photo that I've covered the slight depression of the magiscope stage with a piece of transparency film. This is important when working with water samples because kids will manage to spill everywhere.

Plastic slides are helpful, especially if you can get these with wells. If you don't have slides, you can always use old transparency film that you've trimmed to size, or even the cut bottom of a clear plastic cup.

  Plastic pipettes  help students to transfer water and get small samples. I'm still using the pack of 100 that I purchased 8 years ago!

Some plastic petri dishes can also be helpful for isolating small creatures. Again, I'm still using what I bought years and years ago.

I love "A Guide to Microlife" by Kenneth Rainis, but it's getting harder to find. Don't worry, though; there are plenty of online resources to the creatures that you might locate.

Setting Up

My center can accommodate 3 students at a time. I have 3 microscopes, 2 plastic petri dishes, and 2 droppers.

I've found that using cover plates leads to more mess for my students.

It's important to limit the materials at the center! If you have too many supplies out, kids will use them with abandon. Especially the droppers.

Depending on where you have placed your microscope center, you may want to use masking tape to mark a location in which all materials must be kept. A dry erase board with rules and reminders helps to keep everyone on task.

Most importantly: Have a notebook in which students can record their observations.

Obtaining Samples

Vernal pools are amazing for water samples. A vernal pool is a water source that is only wet during the spring. I always manage to find more creatures in vernal pool samples than in any pond samples.

I live in a rural area, so it's easy to find vernal pools where I can legally take samples. Be sure to get permission wherever you choose to go! Students and other faculty members can be good resources for obtaining samples as well.

I usually get samples in a Tupperware container or mason jar. Standing at the edge of the pool, I let water enter the jar and scoop in a few leaves as well. Once the water settles, I observe the container closely. If I see a few things that look like tiny dots darting through the water, I know that I have a good sample.

If you are getting samples in March or April, when the weather is still cool, you probably won't have to worry about accidentally getting some mosquito larva. At other times of the year, make sure that you don't have wigglers in your sample. They're easy to spot, but would probably lead to some classroom issues....

Introducing the Center

If you have a document camera with zooming capabilities, you can show students some of what is in the sample by displaying it on the projector. I have found that showing the pond water with very little commentary leads to great questions from students: What's that? Where did you find it? Can I see it? Once these questions come out, I introduce the microscope center and briefly outline rules.

For the first sessions, I find some creatures and get them in the microscopes for students to see. Once I've done this, students quickly catch on! When the class has work time, I add the microscope center to the list of allowable activities. I also have a five-minute timer going to make sure that everyone gets equal access.

I also have students put sketches of what they see into their own interactive notebooks. These sketches serve as models for what students will put into the class book of observations.

Putting a single student in charge of making sure that the materials are cleaned up and samples returned at the end of each class is very important. This year, the student in charge takes great pride in making sure that everything is well taken care of.

What will you find? Every year is a little different! Most vernal pools have copepods, which can be seen with the naked eye but come into great detail with the microscopes. This year's samples have a surprising number of daphnia, and students even saw some eggs hatching! We've found that this resource from the Pennsylvania Natural Heritage Program has great information about the invertebrates we see.

Personalized Learning

At first, I make sure that everyone gets a chance to try out the microscopes. As the novelty wears off, a few students continue to check out the water. Some like playing with the droppers. (I think that water play is extraordinarily important and underutilized for students.) Others really like finding new creatures. This week, I've heard, "Mrs. Kissner, I've found a new bug!" at least ten times.

The term "personalized learning" is often used to apply to tedious websites with structured sets of activities. But I think it applies to a microscope center as well! How amazing is it for students who find this engaging to be able to have access to water and microscopes on a daily basis? 

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