LER 9301
Ages Grades
5+ K+
Demonstration Ruler
The Demonstration Ruler is great for modeling linear measurement.
Track measurements from
Suggested Use
Discuss with students some earlier methods of measurement, such as gauging length with thumbs and feet. Guide students in measuring a few smaller objects using the width of their thumbs. Record and compare the results. Lead students to the conclusion that everyone’s thumb width is not the same. Therefore, a “standard” unit, such as inches or centimeters/centimetres, is necessary for everyone to achieve the same measurements.
•Familiarize students to the ruler and its markings.
•Be sure to identify by which units you are measuring (in. or cm).
•If using a white board, draw a line on the board and position the ruler underneath.
•Align the left end of the line to 0 on the left end of the ruler.
•When measuring, always hide the red band from view (as close to 0 as possible).
•Gently slide the band from left to right and align the end of the red band with the end of the line or object being measured.
•Emphasize that the left end of the object or line being measured must always be “flush” (even) with 0 on the left end of the ruler.
•Students should recognize that accurate measurements begin on 0, which is usually
(but not always) on the left edge of the ruler.
• You may need to remove the ruler from the magnetic surface while adjusting the length of the red band.
