Shapely Spider WebsBy Susan L. Cerruti

The Math & Science Centerpresents

Let’s Look at a REAL Spider Web

What shapes do you see?

THINK!

What We Know

A square or rectangle has 4 sides and 4 corners.A triangle has 3 sides and 3 corners.

Same Thing, Different Name

line segmentside

cornerangle

The Point Is…

A point is formed when two lines intersect.

TermsA line segment is_______________.the straight line

between two points.

An angle ismade when two line segments intersect at a point.

_________________.

this special point at an angle is called a VERTEX

Let’s Put it Together

line segmentangle

point

Find the points, line segments and angles of these shapes.

Let’s Look at How a Spider Spins a Web.

What do we see at each stage?

What shape is the web?

What shapes do we see inside of the web?

THINK!

The spider begins with one simple LINE SEGMENT.

These 3 LINE SEGMENTS form the 3 SIDES of a triangle.

The same LINE SEGMENTS also intersect at a POINT to form ANGLES.

The final product—what do we see now?

Make Your Own Geoboard Web Using Your Rubber Bands

THE RULES:– 3 to 10 rubber bands

– no more than 2 rubber bands on one point

– bands should not cross

– your shape must be closed

Examples

Examples

Transfer Your WebCopy your shape onto the graph paper.Use the numbers on your geoboard and

recording sheet to help you.

x

xx

x0 1 2 3 4 5 6 7 8

876543210

0 1 2 3 4 5 6 7 8

876543210

Your Web

Find and count line segments.

Find and count points & angles.

Measure each.

Be Sure to Measure from the 0 on Your Ruler!

0 1 2 3 4 5 6 70

This Side of the Triangle is 7 Inches Long.

0 1 2 3 4 5 6 7

7 in.Write your measurement along the line segment.

What Did We Learn?

What did you learn about your web?

What did you learn about points, line segments and angles?

• Were they the same or different?• Is there a pattern?

Thank You!