BEFORE YOU VISIT THE GARDEN…
Lesson Ideas for Grade 2
Students will understand that koi offspring resemble their parents.
Students will be able to describe the sequence of steps in the life
cycle of a koi fish.
- Picture of Koi (picture #1)
- Fish Life Cycle worksheet (activity page #2)
A typical fish life cycle starts with an egg. The egg hatches into
what is called a yolk sac fry - a larval stage where the fish has
an attached yolk that provides it with nourishment for its first
week or two. The true larval stage begins when the fish has absorbed
the yolk and starts feeding for itself. When the fish gets bigger
and looks very much like an adult, it is considered a juvenile.
Once the fish matures and can reproduce and lay eggs, it becomes
Koi are not live bearers but lay thousands
of eggs in a single breeding. Koi must be at least 3 to 4 years
old and of sufficient size before they breed. Koi require special
water conditions and environment for breeding. The eggs and baby
Koi must be separated from the adult Koi or they will more than
likely be eaten. The baby Koi hatch in about 3 to 7 days depending
on the weather. The survival rate for baby Koi is less than 50%.
- Show students pictures of koi. Ask students what kind of animal
is in the pictures.
- Explain that the animal in the picture is a special kind of fish
called a koi, which they will be visiting on their trip to the Japanese
Gardens. Ask students to volunteer what they think a baby koi would
look like (encourage responses that a baby koi would look like its
- Ask students if they know how a baby fish begins its life (you
may want to refer to the movie “Finding Nemo” if students
are familiar with this story).
- Explain to students that fish start their life as an egg (diagram
this on chart paper or on the board). When they hatch the baby fish
are called “fry.” When they are a bit older they are
called “juveniles (just like people!),” and when they
are full-grown they are adults. Have students repeat the stages
as you write them.
For kinesthetic learners:
Have students act out the stages in a fish life-cycle by first
curling up in a ball to represent the egg, then pretending to hatch
and be “little” for the fry, growing bigger for the
juvenile, and finally swimming around like a “big” fish
as an adult. Be sure to have students say the stages aloud as they
are acting them out.
- At their desks, give each student a copy of the Koi Life Cycles
Worksheet (activity page #2).
- Explain to students that the pictures
represent the life cycle of a koi fish, but that they are all mixed
up. The students are to put it right by cutting out the squares,
and glueing the stages in the correct order on a piece of construction
When all students have completed the activity, have them repeat
the stages from egg to adult, pointing to their papers. Tell students that one koi fish can lay thousands of eggs, which
hatch after only three to seven days. Ask students why they think
koi lay so many eggs. Explain that this is because the adults often
eat the newly hatched fry, and since it takes three to four years
before a koi fish is mature, most don’t survive to become