Level 2+: Germs, Viruses + Fungi Unit

Sometimes the most fascinating topics come in the tiniest packages—microscopic packages even! In this week-long unit, we’ll be introducing your child to the world of microbes and microbiology, spending the majority of our time on the features, differences, and similarities of germs, viruses, and fungi. Get ready to think small. Click here to download this week’s skills tracker.

Note: Occasionally we include project modifications (which can be useful for including younger siblings) and upgrades (for children ready for more). We’ll mark those with the minus (-) or plus (+) symbols.

What you need:

Books (find at your local library or order below on Amazon):

Optional additional books:

Supplies (use what you have, but here are links to shop if you need anything):

What to do:

We recommend doing the below lessons in this order to build on each skill your child will develop, but don’t feel that you *need* to do them in this order. Do what works for you and your child. If they love an activity, feel free to repeat! Not a winner? Skip and try the next thing. Have fun!

Phonics Guide:

New to our phonics guide? Start here. The Phonics Guide this week will highlight the phonogram EW.

Lesson 1:

There is so much to learn about microbes! We’ll begin our week with an overview of this fascinating science. Start by reading The Bacteria Book or It’s Catching!: The Infectious World of Germs and Microbes (or read it here on OpenLibrary). Both books are chock full of information about microbes, so prioritize pages 1-13 in either book for today if your child’s attention span starts to wane.

Activity 1: After reading about the types of microbes, print 3-4 copies of these microbe types cards and play a game of Go Fish! to review them all. This blog post also has a lot of incredibly helpful information about how these different types of microbes exist in the world—and in us!

Activity 2: We’ve learned a lot about microbes already, but there’s nothing like seeing them in real life! A Winogradsky column is a method of growing microorganisms that you can do anywhere if you have some mud, a jar or bottle, and a few other simple supplies. Read this article with your child to learn more about this awesome experiment, and then set up your own with this tutorial. (Download the record sheet workbook in the tutorial to add in some writing practice to your experiment!)

Activity 3: Did you know that microbiology also includes a variety of microorganisms called micro animals? Pages 62 and 63 of The Bacteria Book share more about some of the most common ones, or you can watch this video for more. We won’t spend a lot of time on these creatures this week, but one of the coolest is the super tough tardigrade, or the water bear! If you have access to a microscope, water bears can be relatively easy to find an any environment with moss. This blog post shares how to find them, or you can also watch what the author discovers in her own experiment. (Can’t get enough of the tardigrade? This short video shares more about their special abilities.) Next, make your own tardigrade out of playdough or clay!

Lesson 2:

Today, we’ll be taking a deeper dive into the world of bacteria! Begin by reviewing the bacteria pages from yesterday’s books, and then read Do Not Lick This Book.

Activity 1: This video shares more about bacteria, including some vocabulary words microbiologists are very familiar with. After watching the video, review these terms to see which ones you remember and then look up their definitions online or in a dictionary:

  • organism
  • decomposer
  • pathogen
  • prokaryotic cell
  • nucleus
  • fission
  • bacteria colony
  • DNA

Now that we are more familiar with the parts of bacteria, let’s build this cardboard model to learn more about their functions. (You could also build it out of playdough if your child prefers!)

Activity 2: While many bacteria are helpful, some can make you very sick. Fortunately, bacteria can either be killed or washed away by soap and water, which is why hand washing is so important, especially during cold and flu season! Let’s demonstrate how hand washing keeps us safe with this activity.

Activity 3: Bacteria reproduce by dividing…but the result is that they multiply! Let’s explore this idea and work on multiplying with this math activity. Start by printing this petri dish sheet. The number of petri dishes will represent the first digit in our multiplication problem. Next, give your child beads, small pom poms, or some other small counters to act as the “bacteria” in their petri dish. The number of bacteria will represent the second digit in our multiplication problem.

Next, start playing! You may find it helpful to work your way through different times tables, starting with 1s, then 2s, etc. Write out a multiplication problem for your child on separate paper (for example, 1 x 1). Have your child build this on their sheet by filling 1 petri dishes with 1 bead. Add the total number of beads to find the product. Next, do 1 x 2, and so on. You can also flip the problem (2 x 1) to demonstrate to your child that the order of the digits doesn’t matter in a multiplication problem.

You can also print this times table chart to help your child visualize the patterns of multiplication.

Lesson 3:

For the next two days, we’re going to read true stories about important people in field of microbiology. The first is Ernest Everett Just, a scientist who made some major discoveries about microbes despite facing injustice. Let’s learn more about him in the book The Vast Wonder of the World.

Activity 1: Ernest Everett Just began his scientific exploration by looking more closely at the world around him. Let’s honor his legacy by examining the microbes in our own environment! This experiment provides steps to grow bacteria from your own house (and might be a good motivator for your child to clean up more in the future!). You can use a petri dish kit like this one, or make your own dishes with this tutorial.

Activity 2: Microbiologists like Ernest need microscopes to study tiny organisms like bacteria. Let’s learn more about the parts of a microscope with these copywork printables. Has your child ever seen a microscope in person? Many libraries offer them for rent, or you can start with a kid-friendly version like this one.

Activity 3: As we mentioned, not all bacteria are bad—and some are even downright helpful! Case in point, the bacteria involved in the fermentation of many foods and drinks, like sauerkraut!

Fermentation works by allowing “good” bacteria to grow and stop bad bacteria that would make the food rot from growing. Any fermented food is made by combining water with a fermenting agent such as vinegar or salt, and then letting the mixture sit for days or weeks to ferment.

In particular, sauerkraut forms when “good” bacteria turn the sugars in cabbage into lactic acid, a substance which preserves the cabbage by keeping “bad” bacteria from growing and rotting the food or making people who eat it sick. The good bacteria do not have to be added to sauerkraut because they already exist on raw cabbage. (source)

Next, let’s bring it to life by making our own fermented food with this simple sauerkraut recipe.

Activity 4: Did you know that scientists and doctors have been featured in fine art as well? We see a notable example in “The Anatomy Lesson of Dr. Tulp” by Rembrandt Harmenszoon van Rijn. If you have the book A Child’s Introduction to Art, you can turn to pages 32 and 33 to learn more about this painting and the artist. If not, this article shares more of the history behind it.

Rembrandt’s style of painting in this picture is notable for a variety of reasons discussed in that article, but one reason was his use of contrast. This educational video shares more about contrast and how it works in art.

Finally, let’s explore contrast with an art project. Start by having your child draw an object that might sit on a table (it could be a vase of flowers, a bowl of fruit, a fish bowl, etc.) using only a black marker on white paper. On a separate piece of paper, have them draw the backdrop of their picture (including the table top) using only brightly colored markers (permanent markers will have the best effect).

To put them together, cut out the black and white object and glue it onto the backdrop. Discuss how the contrast of black and white and color makes each part of the picture stand out more.

If your child enjoys this craft, they could make a second version where the object is colorful and the background is black and white.

Lesson 4:

Another common microbe virtually everyone has experienced? The virus! Viruses are much smaller than bacteria, and they aren’t able to reproduce without help. Read the section of your microbe book that talks more about viruses (or you can read this article or watch this video if you weren’t able to get either book), and then read June Almeida, Virus Detective! The Woman Who Discovered the First Human Coronavirus.

Activity 1: Viruses come in a variety of shapes and sizes—you can see some of the most common shapes in your book or in this article. For our first activity, let’s build a model of one of the most common types of virus, the bacteriophage! Begin by printing this template to create the shell, or capsid. (You can print on colorful paper, or let your child color their own pattern on the template before folding.) Next, cut out the shape and fold along each line, putting glue or tape on the gray tabs to hold the shell together. Cut out one triangle segment so you leave a window into the shell. It should look like this:

Create the virus’ tail and tail fibers with a straw and six pipe cleaners, and then attach the tail to the capsid. Fill the capsid with bundled up yarn, paper cuttings, or another pipe cleaner to represent the DNS, which stores instructions for building a copy of the virus. Finally, label the capsid, DNA, tail, and tail fibers, like this:

Activity 2: Next, let’s compare and contrast bacteria and viruses using this printable. Use your book as a reference or watch this video to help your child figure out the similarities and differences between these microbes.

Activity 3: Let’s practice this week’s featured phonogram with a little pretend play! Start by printing these pages. Cut out the microbe cards and write an EW word on the back of each one. Here are some examples:

  • blew
  • brew
  • chew
  • drew
  • spew
  • grew
  • new
  • dew
  • flew
  • knew
  • phew
  • stew
  • newt
  • whew
  • pew

Next, put each microbe word-down in a petri dish. Have your child pretend to be a microbiologist and “discover” and read the word on the back of the microbe!

Activity 4: Now that we have a solid understanding of the basics of bacteria and viruses, let’s invent our own! Have your child draw a picture of their bacteria or virus (noting the parts to review what we’ve learned) and decide:

  • is it a helpful or harmful bacteria or virus?
  • what does it do?
  • who does it affect?

Let your child get as silly and creative as they want with their creation! Do they want to create a bacteria that gives people super powers? Do they want to invent a bacteria that grows from farts? Nothing is off limits for this creative exercise!

Lesson 5:

For our last day of activities, we’ll explore another amazing microbe: fungi! Scientists estimate that there are around 5.1 million types of fungi in the world. (source) Some are helpful, some are harmful, but they all share some important characteristics. Let’s learn more about them in our book book (look for the pages that discuss fungus), and then read Humongous Fungus or The Fungus Among Us! for more.

Activity 1: Would your child like to grow their own mushrooms? This tutorial explains how to grow oyster mushrooms you can eat! Alternately, you can grow mushrooms with this kit.

Activity 2: Yeast is an important fungus that helps us make a variety of delicious foods and drinks. Let’s learn more about how yeast plays a role in fermentation in this video. Next, let’s bring it to life with this experiment!
(+) Another food that relies on yeast? Bread! If your child is up for another experiment, help them see how yeast helps bread get it’s signature light, fluffy texture in this experiment.

Activity 3: Mold also plays an important role in making cheese. To make cheese, you take the fats and proteins of milk and introduce microscopic molds, bacteria, and/or yeasts. Along with naturally occurring microbes in the environment, these cultures help coagulate the milk into curd and release enzymes while the wheels are aging. Those enzymes break down fat and protein to create supple textures and lively flavors and aromas over time. This article shares more about the steps of cheesemaking and how they involve mold, as well as what to do if you find mold on your cheese. It’s a very helpful read!

Gorgonzola is a blue variety of cheese made using a type of mold called Penicillium roqueforti, which is responsible for its distinct taste, smell, and appearance. Unlike other types of mold, the types of Penicillium used to produce blue cheese do not produce mycotoxins and are considered safe to consume. Has your child tried gorgonzola? Let’s explore this unique flavor with this simple, no-cook recipe.

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Published by The Learn + Live Letter

The Learn + Live Letter is a play- and project-based homeschool curriculum for children ages 3-12.