There's this great sketch by dhabecker, Arrange fractions, decimals, and percents, [url]http://www.geogebratube.org/material/show/id/15308[/url] that was helping my students.
He figured out a clever way to generate 4 rational numbers, to sort them by dragging, and to check if they were in the right order.
Then John Golden added colors, a button for new numbers, and a way to check other than all right or not. (Inspired by the great game Mastermind.)
Then now this scheme is modified to assess students' number sense of surds (to familiarize them with irrational numbers under the topic Real Numbers).
Instead of using decimaltwo, surd1 was the randomized value used.
