Math = Love: Rationalizing the Denominator Practice Activity

Tuesday, March 21, 2017

Rationalizing the Denominator Practice Activity

I already posted about our recent Algebra 1 unit on radicals.  But, I just realized I forgot to share the question stack I created to help my students practice rationalizing the denominator. 

Question stacks are one of my favorite practice structures.  Students are given a double-sided deck of ten cards.  One side of the card features a question.  The other side features the answer to a DIFFERENT question.  

Students begin the activity by turning over all of the cards to reveal ALL of the answers.  I tell my students this is their answer bank.  

Then, students flip over one card of their choosing.  This will be their first problem to solve.  When students find the solution, it should be in the answer bank if they have done everything correctly.  They pick up the solution card and flip it over to reveal the next question. 

I love question stacks because they are self-checking.  This means I can focus my help on the groups struggling the most.  The answer bank gets smaller and smaller with each question which helps build student confidence.  

Here are the questions.  I put boxes around the questions to make them easier to spot. 


And, here's the answer bank.

 Here are some pictures of my students in action: 

I have uploaded the file for this question stack here.  

Want more question stacks? 


  1. Thanks for explaining how questions stacks work. Something I might want to try in German...

  2. There are two of the same answers (square root of 6 over 3). It makes it not work out if they pick the "wrong" one.

  3. Thank you! I used the question stack problems as notes practice problems. Very quick and helpful.