Hands-On Science! All About Whales

In this science unit, we will learn all about whales, and especially about blue whales, through hands-on activities. We will learn about their size, what they eat, how they eat, and how they survive in cold ocean waters.

Recommended Reading:

My top two recommendations for learning about blue whales are:

Big Blue Whale by Nicola Davies

The Blue Whale by Jenni Desmond

I highly recommend reading at least one of these books along with this unit!

For learning about whales in general, here is a list of great children’s books:

the-best-childrens-picture-books-about-whales: Hands-On Science! All About Whales

How Big is a Whale?

For this activity, you will need:

• a tape measure
• a tea cup (or cup of similar size)
• sidewalk chalk

Have you ever seen a whale? Can you imagine it’s size? Whales are very big animals! In fact, blue whales are the largest animals on earth – by a lot! In fact, just the tongue of a blue whale is as heavy as an elephant! And it’s heart is as big as a car! It’s eye is the size of a teacup (pass around the teacup and think about having an eye that big). An adult blue whale can be up to about 100 feet long. Let’s get an idea of how big that really is.

Measure a Whale

Now it’s time for the tape measure and sidewalk chalk! Go to a large open space outside – you’ll need a long stretch, such as a parking lot or sidewalk. Mark a starting point and write “blue whale” with the sidewalk chalk. You might want to place something on that mark, so it’s easy to see from a distance. Now measure 100 feet from that point. Draw a line from the beginning point to the 100 feet mark. That’s how big a blue whale is!

*If you are really ambitious, you can try drawing a life-sized blue whale. If you decide to do this, here are a few helpful dimensions: a blue whale’s tail fluke is 20- 25 feet wide, it’s mouth is about 20 feet long, it’s flippers are about 10 feet long, and it’s eye is a little over 4 inches wide..

Let’s compare some other whales to the blue whale.

Draw a new line for each of the following whales next to the blue whale line (or drawing if you chose to draw it) and label them.

The very smallest whale, the dwarf sperm whale, is about eight feet long.

Narwhals can be up to 18 feet long.

Orcas are about 30 feet long.

Grey whales can be about 50 feet long.

Sperm whales can be up to 62 feet long,

So whales come in lots of different sizes!

Baleen or Teeth

Whales are divided into two main groups: baleen whales and toothed whales. Baleen is a set of stiff bristles that are made up of the same stuff your fingernails are made of. The baleen comes down from the top of the whales mouth and acts as a filter to catch tiny sea creatures for the whale. Something interesting about whales is that the largest ones don’t have teeth! (Note – the sperm whale is an exception to this – it is a toothed whale and it is one of the larger whales). Which means that even though they are very large, the food that they eat is very small. Blue whales are baleen whales. So are grey whales, humpback whales, and others. To eat, the baleen whales take a huge mouthful of sea water (and to give you an idea of how much water that would be – a blue whale can hold 10,000 gallons of water in its mouth, which is about half of the water in an average swimming pool). As the whale pushes the water out of its mouth, any small ocean animals get caught in the baleen, and the whale pushes them to its throat with its tongue so it can swallow them.

Meet the Krill, and Eat the Krill

For this activity you will need:

• krill (you can find these at a pet shop in the freezer – I got mine at Petco) – be sure to thaw the krill before the activity
• a plastic pencil box
• a comb around 8 inches long
• hot glue
• duct tape

To prepare for the activity, glue the comb onto the top inside edge of the long side of the pencil box. Cut a piece of duct tape to about 7″ long and a second piece about 5″ long. Center the 5″ piece on the middle of the 7″ piece and stick them together. Stick the duct tape to the top of the pencil box to create a handle. This will be your whale mouth.

Fill a large bowl or container with water. Have the krill nearby.

The animal that a blue whale eats is called krill. It’s like a small shrimp and is pink in color (show the krill and allow your students to touch them if they would would like to). Swarms of krill swim in the ocean where blue whales feed, so many that sometimes the water looks pink! To demonstrate how the blue whale eats them, we are are going to catch some krill!

Pour the krill into the bowl of water. You will need to stir them up before trying to catch them because they will sink. Now, have a student place their hand in the handle on the whale mouth and use their thumb to open and close the “mouth.” Ask them to catch as many krill in the mouth as they can and then let the water drain out through the “baleen” (the comb). That’s how baleen whales catch their food!

Bring on the Blubber!

For this activity you will need:

• a small container of shortening or lard
• a spoon
• a disposable glove (one per child)
• a sandwich bag (one per child)
• a large bowl of ice water

Blue whales catch up to about three truck loads of krill every day! They need all those krill to help them build up fat, which they need for three reasons. First, the whales go without eating for months when they are migrating and having babies, and they use their fat stores for energy during this time. This is important because blue whales have their babies in warmer water where there isn’t much for them to eat. Have your child scoop a spoonful of the shortening and drop it into the water. It floats! The thick layer of fat under a whales skin helps it to float. Can you guess what the third purpose of the fat is? Let’s do an activity to find out!

Have each child place a glove on one hand. Fill a sandwich bag halfway with shortening, one per child. Have each child place their gloved hand into the shortening in the bag and squish it around to cover the gloved hand with shortening. Have each child take turns placing both hands in the ice water. How do your hands feel? Do you know now what the third purpose of the fat is? To keep the whale warm in the icy cold ocean water!

*Note – this activity is an adaptation of an activity described on page 54 of Exploring Creation with Zoology 2: Swimming Creatures of the Fifth Day

Now that you have learned all about whales, you can make a whale craft to help you remember what you learned. We did the paper plate whale craft in the video below and really enjoyed it!

I hope you had fun with this science unit! Thanks for learning with us!