1
U n t er r i ch t spl a n
Id e nt if y ing Po l y g o ns
Altersgruppe: 2nd S t andar d
NCERT: C 2.G.S S U.5
Online-Ressourcen: Do n' t P o ke A r o und
Opening
T eacher
present s
St udent s
play
Act ivit y
8
10
10
15
4
min
min
min
min
min
Closing
ZIE L E :
E x pe r i e nc e classification
P r ac t i c e identifying polygons
L e ar n geometry vocabulary
De v e l o p geometry skills
Ope ni ng | 8 min
• Have the students work in pairs. Distribute the following six shapes and
blank paper to each pair.
Copyright 2015 www.matific.com
2
.
• Ask the students to put the shapes together to make as many polygons as
they can. They can use all of the shapes or just some of them. Once they
have formed a new shape, they should trace it on the paper.
o Possible responses:
.
• Once the students have completed the assignment, discuss.
o Ask a student to come to the board to draw one of the shapes she has
drawn.
o When she is finished, call on another student to draw a different polygon
that he created on the board.
o Continue to call on students until there are many different polygons drawn
on the board.
o Say: Today, we are going to look at the sides and corners of our polygons.
The mathematical term for side is edge and the mathematical term for
corner is vertex and for corners is vertices. How many edges does a triangle
have?
A triangle has three edges.
o How many vertices does a square have?
A square has four vertices.
o Using the drawings that the students have made on the board, review the
number of edges and the number of vertices in each polygon.
T e ac he r pr e se nt s Do n’ t P o ke A r o und I | 10 min
Copyright 2015 www.matific.com
3
• Present Matific’s episode Do n ’ t Po k e A r o u n d I d e n t if y in g Po ly g o n s
to the class, using the projector.
The goal of the episode is to classify polygons by their number of edges and
vertices.
E x a m p le :
• Say: Please read the instruction.
o Students should read the instruction at the bottom of the screen.
• Ask: Are we looking for the number of sides or the number of corners?
o Students should respond based on the instruction.
• Ask: Which polygons should we click on?
• Click on all the polygons that the students identify.
If you click on a polygon that is incorrect, a small “X” will appear, and a new
polygon will fall from the top of the screen.
• When you have clicked on all of the polygons that the students have
identified, click on .
If you have identified all of the qualifying polygons, the episode will proceed
Copyright 2015 www.matific.com
4
to a new situation.
If you have not identified all of the qualifying polygons, the instructions will
wiggle.
• The episode will present a total of five situations.
S t ude nt s pl ay Do n’ t P o ke A r o und I | 10 min
• Have the students play Do n ’ t Po k e A r o u n d I d e n t if y in g Po ly g o n s on
their personal devices. Circulate, answering questions as necessary.
Copyright 2015 www.matific.com
5
A c t i v i t y | 15 min
• Have the students work in pairs. To each pair, distribute scissors and a
handout with the following quadrilaterals.
.
• Say: We can sort polygons by the number of edges and the number of
vertices. But we can sort even further. All of the polygons on the handout
have four edges and four vertices. How would you categorize the
quadrilaterals on your paper? Cut them out and put them into categories.
• Once the students have sorted the shapes, discuss.
o Ask: How many categories did you make?
Responses may vary.
o Ask: What names would you give to each category?
Responses may vary. A possible response: square, rectangle, trapezoid, and
parallelogram.
o On the board, write the categories that the students develop.
o Distribute larger versions of the 12 quadrilaterals that were on the handout
to 12 students. Ask students to come to the board one at a time and tape
their shape in the correct category.
o Discuss characteristics that make one category different from another.
Copyright 2015 www.matific.com
6
C l o si ng | 4 min
• Ask: What does the word edge mean?
o An edge is the side of a shape.
• Ask: What does the word vertex mean?
o Vertex is another word for the corner of a polygon.
• Draw the following polygons on the board:
.
• Ask: Which of these polygons has more than three edges?
o The second, third, fourth, and sixth polygons (the pentagon, rectangle,
pentagon, and hexagon) have more than three edges.
• Ask: Which of these polygons has exactly six vertices?
o The sixth polygon (the hexagon) has exactly six vertices.
• Ask: Which of these polygons has exactly three vertices?
o The first and the fifth polygons (the triangles) have exactly three vertices.
Copyright 2015 www.matific.com