Image of erasers that look like rubik's cube, monkey, giraffe, and ice cream cone
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Math,

The Amazing Eraser

What you never knew about your pencil’s perfect partner

By Jess McKenna-Ratjen | Illustrated by Tony Trimmer
From the September 2024 Issue
Key Focus Area: Measurement and Data,
Standards
  • NGSS
    Core Ideas: ETS2.A, ETS2.B, ESS3.A
  • CCSS
    Math: 3.MD.B.3
  • TEKS
    Science: 3.4A, 4.4A, 5.4A, 6.4A

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How It Works

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When you write, graphite from your pencil tip gets onto the paper. Rubbing pencil markings with an eraser lifts the graphite from the paper.

By the Numbers

It takes about 1,300 strokes to use up the whole eraser on the top of a pencil.

People around the world spent an estimated $2 billion on erasers in 2021.

From a Volcano to Your Eraser

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Most pink erasers contain pumice, a gritty volcanic rock. It forms from cooled, hardened lava. The pumice in erasers helps scrape your pencil marks off the page.

Then & Now

Rubber erasers were an accidental invention!


First, people used bread to erase pencil marks.


Around 1770, an engineer accidentally grabbed a piece of rubber instead of bread to erase his work. The rubber worked better!

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TODAY, most erasers are made of plastics, like vinyl. This makes fun shapes and designs possible.

Find three different types of erasers. Which do you think will work best? Plan an experiment to find out!

Activities (2)
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Skills Activities
Answer Key (1)
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