Classifying Rational & Irrational

At the beginning of the year one of the first things we do in Algebra 2 is go over types of numbers. We classify natural, whole, integers, rational, and irrational numbers. The next day we do a group formative assessment where in a group they take turns organizing different numbers into rational/irrational numbers. Then I give each of the groups a get a sheet where they have to organize a list of numbers into rational/irrational and explain why.

Students did an excellent job discussing the numbers and classifying them.

The Math Assessment Project has other amazing resources like this one at their website.

Rational or Irrational? That is the Question.

One of my favorite beginning of the year activities is a card sort that we do that reviews if different numbers are irrational or rational. Students are placed into groups of 4 and have to reason with one another about the placement of each number.

Here are a few groups placing their numbers:

Here are some example numbers we had:

Here are some finished products:

This was a great activity to get students use to classroom procedures and routines.  You can find the activity here: http://map.mathshell.org/lessons.php?unit=9105&collection=8&redir=1

The activity was in groups and went through each one large group.  I had students explain why they put them in certain categories and had a classroom discussion if they agreed or not.  Some could be put into more than one category depending on the explanation.  It was a fun experience.