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Parent Graphs of Trig Functions Clothespin Matching Activity

This parent graphs of trig functions clothespin matching activity has been in the making for multiple years. Several years ago, I discovered a Parent Graphs of Trig Functions Worksheet from Robyn Wolfe of Carlisle Schools.

trig graphing matching activity

Overview of Activity

I used the worksheet with great success in my pre-calculus class, and I remember writing a note on my to-do-list at the time that it would make a great interactive group activity. I wanted my students to be able to get feedback on a question-by-question basis instead of just doing the entire worksheet and turning it in for a grade.

Well, the pandemic ended up happening which required me to teach my trigonometry lessons without any group activities at all. This year, I was finally able to make this interactive clothespin matching activity to share with you!

The majority of my focus in our graphing trig functions unit is on sine and cosine graphs. But, I always do want to make sure that my pre-calculus students are exposed to the parent graphs of all six trig functions.

We use our unit circles to graph the parent functions of the ach of the six trig functions.

parent graphs of trig functions notes

Then, I had my students complete this clothespin matching activity as they reference the parent graphs they just drew in their notes.

I used the questions from the worksheet I found online to create individual task cards. The original worksheet would give students a description and ask them to list all the trig functions with the given characteristic.

parent graphs of trig functions worksheet
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In my group activity version of this worksheet, students are given the same prompts. I put circles on the bottom of the task card to indicate how many trig parent function graphs match the given characteristic.

Parent Graphs of Trig Functions Clothespin Matching Activity

Students then work in groups to determine which trig clothespins should be attached to the card.

Parent Graphs of Trig Functions Clothespin Matching Activity

Activity Set-Up

To set up this activity, I typed up all of the graph descriptions with circle placeholders.

cards for Parent Graphs of Trig Functions Clothespin Matching Activity

I printed these, ran them through my laminator, and then cut them apart with my paper chopper.


drawing of laminator machine with text "laminating recommendations"

A laminator is a MUST-HAVE for me as a math teacher! I spent my first six years as a teacher at a school with a broken laminator, so I had to find a way to laminate things myself.

I’ve had several laminators over the years. I currently use a Scotch laminator at home and a Swingline laminator at school.

I highly recommend splurging a bit on the actual laminator and buying the cheapest laminating pouches you can find!

I also printed up tables with the names of all six trig functions on them. I printed these on colored paper and laminated them as well.

laminating cards for Parent Graphs of Trig Functions Clothespin Matching Activity

Originally, I was going to cut apart the rectangles with the trig functions on them and glue them to wooden clothespins.

supplies for Parent Graphs of Trig Functions Clothespin Matching Activity

But then I remembered that I had some adhesive velcro dots in the cabinet that I had purchased from Amazon for a different project.

rolls of velcro dots

I ended up taking the velcro dots and placing half of the velcro on the clothespins and the other half of the velcro on the back of the trig function labels.

velcro dots on clothespins

With this set-up, I can remove the labels from the clothespins and reuse them for another clothespin matching activity in the future if I think of another activity that I want to create.

Parent Graphs of Trig Functions Clothespin Matching Activity

I have my desks in my classroom set up in six groups of five, so I ended up making six different sets of clothespins so each group would have their own set.

clothespins on desk

If you don’t plan on switching out the clothespins to use them for another activity, I would definitely skip the velcro step and just hot glue the laminated cards directly to the clothespins.

clothespins in bags on desk

Another option would be to skip the clothespins altogether and just do the velcro on the laminated rectangles of paper.

Activity Instructions

After reviewing the six trig parent functions with students, explain that you are going to do an activity to test their knowledge of trig functions by asking them to determine which trig functions match a given description.

I printed two sets of the challenge cards which I kept in a very unorganized pile on my desk during the activity. It started out organized. However, I found that any organization goes out the window when students are racing to find a certain challenge card.

Parent Graphs of Trig Functions Clothespin Matching Activity

Each group was given a bag of clothespins and asked to send a member of their group up to my desk to grab a challenge card to begin with.

That student takes the challenge card back to their desk where their group works together to determine which trig parent functions match the given characteristics on the card.

When a group thinks they have it figured out, they bring their card and attached clothespins up to my desk to have it checked.

Parent Graphs of Trig Functions Clothespin Matching Activity

If their answer is correct, they remove the clothespins and grab a new challenge cards.

If their answer is incorrect, they go back to their groups to re-examine their graphs of parent functions to try and figure out where they might have gone wrong.

Parent Graphs of Trig Functions Clothespin Matching Activity

Since there are twenty different challenges to work through, it can be very difficult for students to keep track of which challenges they have completed and which ones they have yet to do.

I created a stamp sheet for each group to carry with them. When a group successfully completes one of the challenges, I stamp the number corresponding to the challenge they completed.

Parent Graphs of Trig Functions Clothespin Matching Activity

A 50-minute class period was the perfect amount of time to the do the page of notes where we graphed each parent function and this activity. Not all of the groups completed all 20 challenges, but several groups finished in each class period.

In one of my class periods, we had only a 40-minute period due to a school event, and my students felt very rushed for time. They were very disappointed that they were not able to finish the entire activity.