This can be used to demonstrate the existence of decimal numbers.
Prerequisite is that learners have some prior understanding of representation of whole numbers on a number line.
By zooming in, the decimals in tenths, hundredths, and up to thousandths are revealed around the region on the number line where the point A is placed.
You can click on the point A and drag the point to change its position, with your mouse.
Prepare your own lesson plan to guide the students exploration.
I do appreciate feedback for further improvement of this resource.
(email me at lewweisern@gmail.com, or find me in Geogebra forum - "lewws" )
File updated 15 Mar 2016 - revised number of decimal points of number A displayed and conditional display parameters.
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Other examples of number line tools (non Geogebra)
https://www.mathsisfun.com/numbers/number-line-zoom.html
A comprehensive number line tool at
https://apps.mathlearningcenter.org/number-line/
See http://www.antonija-horvatek.from.hr/applets/decimal-numbers/1-Decimal-numbers-on-the-number-line.htm for Antonija Horvatek's excellent webpage lesson on Decimals on a number line.