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How is your life like an alligator's life?
Life Cycles Unit | Lesson 1 of 5

How is your life like an alligator's life?

Life Cycles Unit | Lesson 1 of 5
Lesson narration:
Scroll for prep
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DISCUSS:

What's your favorite thing you can do now that you couldn't do when you were a baby?

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DISCUSS:
Which birthday buddy do you think will change the MOST
as they grow into an adult?
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DISCUSS:

How could you draw a picture that shows how you’ve changed since you were born?

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Step
01/22
Find a partner.
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Step
02/22
The first two birthday buddies you’ll look at are a squirrel and an
ostrich. There are many ways a squirrel is very different from an
ostrich. Discuss with your partner:
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Step
03/22
You probably came up with many ways these animals are different.
Here’s a tougher question. There are ways that a squirrel and an
ostrich are the same. Discuss with your partner:
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04/22
Get your supplies.
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05/22
Have one person cut the Animal Cards sheet in half, like this.
Then each of you take half and cut along these dark lines.
You’ll end up with four animal cards.
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06/22
Find the cards for ostrich and squirrel. You will add one of these
animals to your timeline. Your partner will add the other to their
timeline. Decide who will add ostrich and who will add squirrel.
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07/22
Both: Cut along all the dotted lines on your animal card.
You’ll cut out your animal’s name and some important events in your
animal’s life.
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Step
08/22
Get your Birthday Buddies Timeline. Glue the name of your animal
where it says “Birthday Buddy #1.” To keep the glue off your table,
use a scrap piece of paper, like this.
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09/22
Look at the boxes from your animal card. Find the one marked with a
0. That’s when your animal was born. Match up the 0 on the box and
the 0 on the timeline. Glue the box in place, like this.
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On your timeline, 1 marks your animal’s first birthday, 2 marks their
second, and so on. Match numbers on the other boxes from your
animal card with numbers on the timeline. Glue the boxes in place.
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11/22
The timeline shows ten birthdays. Squirrels live for about ten years,
so the squirrel’s last birthday fits on the timeline. But ostriches can
live for 70 years! Discuss with your partner:
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12/22
You’d have to make the timeline 7 times longer—like this! That’s a lot
of paper. So we suggest you just glue the ostrich’s arrow down, like
this. It points to where 70 would be if we made the timeline longer.
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Now you can see some important events in your animal’s life. Taking
turns, tell the story of your animal’s life to your partner. Start with
what happens at 0, then move from one event to the next.
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Now you’ve told your animal’s life story and listened to the life story
of your partner’s animal. Let’s think about what’s different in the life
stories of these two animals. Discuss with your partner:
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15/22
Here are some of the things we noticed. Ostrich babies hatch from
eggs and squirrels don’t. Ostriches take much longer to grow up and
have babies. And ostriches live a lot longer than squirrels!
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Now let’s look for ways that the life stories of the ostrich and the
squirrel are the same. Look at the events in the lives of these two
animals. Discuss with your partner:
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Both animals are born. Both animals get bigger and bigger as they
grow from babies to adults. Both animals have their own babies when
they grow up. And both eventually reach their last birthday.
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Get your other animal cards. Decide who will add the bullfrog to their
timeline and who will add the Hercules beetle. I’ll set a timer to give
you 30 seconds to decide.
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19/22
Cut along all the dotted lines on your animal card.
Glue the name of your animal where it says “Birthday Buddy #2.”
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Look at the boxes from the animal card for Birthday Buddy #2.
Match numbers on the boxes with numbers on the timeline.
Glue the boxes in place, like this.
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21/22
Take turns telling the life stories of the animals you and your partner
added—the bullfrog and the Hercules beetle. Start with what
happens at 0, then move from one event to the next.
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You can probably see lots of differences in the life stories of the four
animals. But instead of looking for differences, look for events that
are the same in the life stories of all four animals. Discuss:
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DISCUSS:

If all animals eventually die, will animals exist in the future?

How do you know?

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DISCUSS: How could you add to your timeline to show what happens to your birthday buddies’ babies after they are born?
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birth


1 of 13

a stage in the life cycle of every living thing that is the beginning of its life
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offspring


2 of 13

babies
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growth


3 of 13

a stage in the life cycle of every living thing when a baby grows to an adult
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metamorphosis


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a process where an animal's body transforms dramatically, such as a caterpillar turning into a butterfly
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chrysalis


5 of 13

a stage of the life cycle between larva and adult, specifically for butterflies
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reproduction


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a stage in the life cycle of living things when they have offspring
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death


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a stage in the life cycle of every living thing that marks the end of its life
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life stage


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one of the steps of the life cycle
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timeline


9 of 13

a picture that shows the passing of time as a line, often with events labeled along the line in the order they happened
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pattern


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something that happens again and again and again in a way that can be predicted
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cycle


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a set of events that repeats in the same order over and over
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life cycle


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the stages of life, including birth, growth, reproduction, and death
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swamp


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a habitat covered in water and filled with many trees
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Lesson narration:

Grade 3

Life Cycles

Animal Life Cycles

3-LS1-1

Activity Prep

Print Prep

In this lesson, students explore animal life cycles by thinking about their birthday buddies—all the animals that were born on the exact same day as they were born—and what happens to those birthday buddies over the course of their lives. In the activity, Birthday Buddies Timeline, students develop a model to compare the life stories of different animals. Using this model, students discover that although the lives of animals can be very different, they all have in common birth, growth, reproduction, and death.

Preview activity

Exploration

15 mins

Wrap-Up

10 mins

Grade 3

Life Cycles

Animal Life Cycles

3-LS1-1

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