If there’s one thing that high school geometry students need a ton of practice with, it is geometry proofs. Proofs are a brand new, and very abstract concept for our geometry students. Geometry teachers could very easily spend the better part of the school year just working on proofs. That’s why teachers need a great go-to strategy for geometry proofs practice. To help my students, I created geometry proofs practice cards.
Set Students Up for Geometry Proofs Practice Success
Proofs are overwhelming for students. Throughout our time writing geometry proofs, I provide my students with geometry proofs lists and geometry proofs cheat sheets. Students usually struggle trying to find reasons for geometry proofs, and they get to use these as a reference while completing proofs on their own.
The Traditional Method of Proof Practice
In my first years of teaching high school geometry, I implemented the traditional practice activities for proofs. I gave students an envelope with all of the statements and reasons for a proof cut out on paper strips for students to match and sequence. Students do well with these activities. These activities are great when students first learn to do proofs. However, matching and sequencing statements and reasons into a proof does not translate to students being able to write their own proofs. After trying these activities, I would give my students a geometry proofs worksheet, and they would be completely lost.
Geometry Proofs Practice Cards
My students are most successful with proofs after using geometry proofs practice cards. The proofs practice cards function like task cards. A group of students have access to a set of cards to use as they need them. Showing each proof on a single card allows students to focus on one proof at a time.
When we use proofs practice cards, I give each student a packet of proofs to complete. My students sit in groups. This permits students to work together if they so choose, but each student is responsible for turning in their own packet. Each group has a stack of proof practice cards. As I introduce the activity, I tell students that they should try each proof on their own, or with a partner, and then resort to using the proof practice card if they get stuck.
Practice with Geometry Proof Cards
The proof practice cards are double-sided. The front of the card is labeled with the proof number. The back of the card shows the proof in a two-column format with information missing. The hints include the number of steps to complete the proof, some statements, and some reasons. Sometimes the reasons are fill-in-the-blank. For example, the reason may say “definition of _________.”
While my students are working on their proofs, I visit one group at a time to answer questions and guide students to complete proofs. (Mostly, I have to remind students to mark their diagrams.) I use this activity for congruent triangles, CPCTC proofs, and parallelogram proofs. Afterward, many students are able to complete a proof on their own.
Students Gain Confidence & Independence
After using this activity for a few years, I will never go back to using the proof strips. While students initially need a lot of help to complete proofs, they need to be able to complete proofs on their own in the end. Proof cards provide a scaffolded practice structure where less information is given to students as the proofs become more complicated, allowing students to gradually become more independent in completing proofs.
Would you like to try Geometry Proofs Practice Cards with your students? Check out the proofs practice cards available in my TpT store. Congruent Triangle Proofs, CPCTC Proofs, Parallelogram Proofs, and a money-saving bundle are currently available. Make sure you follow me for future updates.
My friend Lindsay Bowden shares 5 ways she teaches proofs in this blog post.
For details abut how I teach geometry proofs using interactive notebooks, check out this video:
For more interactive notebook information, you can check out how I set up my interactive notebooks.
