It's not a "sin" to do Trigonometry, It's a "Sine" of new content!

One of the biggest jokes in my class when I teach the Right Triangles and Trigonometry unit in my Geometry class is how to pronounce "sin".  I inevitable end up telling my students (jokingly of course) when they pronounce it as "sin" and not "sine" that it is not a sin to do Geometry.  Most of them giggle and then we discuss how to properly pronounce Geometric terms. 

One of the biggest problems I find in my Geometry class is a students inability to define the terms.  I cannot begin to count the number of times that I found it necessary in past years to redefine terms that we have already covered multiple times (think alternate interior angles versus consecutive interior angles).  Since vocabulary is so important in both general content and problem solving as well as on state testing I decided to talk the issue head on.

So in that spirit I want to share with you my top four ways to reinforce Geometrical vocabulary and to help students to retain it beyond a single unit.

Geometry B Bundle

Geometry A Bundle

1)  Illustrate, illustrate, illustrate!   I have embarked on a quest to illustrate our terms whenever possible.  I created sets of posters for every unit that we will study throughout the entire course.  Each poster is 8.5 by 11 and includes the definition, a labeled illustration and and pertinent facts.  I print them on card stock, laminate and hang them around the round grouped by unit.  I leave them up the entire trimester and refer to them constantly.  (I have them in my TeachersPayTeachers store in money saving bundles).

Triangles and Congruency

2)  Practice leads to retention!   I start every unit by asking my students to complete a vocabulary assignment (I usually give it to them as their assignment to complete after finishing the prior unit assessment).  Each vocabulary assignment includes a few pages where students give the definition, an illustration if necessary and any prior knowledge they might have.  I also include a crossword puzzle and a word search.  The students enjoy usually enjoy doing these assignments since it helps to give them a preview of what the unit will be covering. We refer back to these vocabulary lists as the unit goes on and students refine their definitions as the unit progresses. 

Congruency Vocabulary Activity

Early Concepts Bingo

3)  Play games or do activities!  Whenever possible I do vocabulary activities or play vocabulary games with my students.  I created some cut, paste and match activities for my students that require them to match the term, definition, a diagram and a label.  The students LOVE doing these.  It helps to tie all of the pieces together for them!  Additionally, we play vocabulary bingo games too.  I play one of two ways.  I either give them cards that are the terms or cards that are a diagram of the term.  Depending on what I gave them as a card, I will either read the term, read the definition or a project a diagram of the term.  We also play Kahoot (this does require you to have access to either I-Pads or smartphones and a projector or smart-board with internet access) which is the best online game to play I have seen in many years of teaching. 

4)  Get the students talking about the vocabulary and using it correctly!  I'm pretty sure that at times my students are either rolling their eyes when I'm not looking or thinking I'm slightly strange but I do not let them get away with skipping over the vocabulary during classroom discussions.  I ask them questions like "why can you do that" or "what geometry concept is being illustrated/applied" leading them back to the vocabulary all the time.  "Tell me why" is so commonly said in my classroom that after a couple of weeks I find students saying "wait, let me tell you why" or asking each other why!  I love it when it works!

Whatever works the best for you, embrace it!  The more you can get the students to understand the why, the what and the how behind what they are doing, the better they get at it!  In my opinion, students need to use mathematical vocabulary to truly retain the material.