Welcome to Proofland!
Teaching triangle congruence proofs in Geometry can be challenging and also fun. I love seeing students’ faces light up when it clicks for them!
Here are some ideas to help make it easier for you.
Warm up with Uno
I love this strategy for introducing proofs. My students might not have played traditional cards, but most had played Uno, and the ones who hadn’t quickly caught on to the concept.
Mix it up
Here are two free proofs you can use (comes in full color and black & white). They’re part of the full Google folder of high school math teacher materials I have available just for my Kennedyfamfive travel buddies.
These two proofs are also part of the full set of task cards and scavenger hunt you can get here.
An online scavenger hunt is a fun way for students to practice proofs. This one comes with the online (Google Forms) version that’s completely done-for-you. You just assign it to your kids.
It also comes with a printable version if you want to do the scavenger hunt in person with your class. (Print in full color or black & white.)
If you need just the proofs, without the specific questions, those are included, too!
And, yes, there’s an answer key with worked out proofs so that you don’t have to do that ahead of time, either!
Tell a story
Have students think of a time when they successfully convinced their parents to let them do something…such as going to a party, driving somewhere by themselves, etc…ask, “What did you do when your parents said yes?”
Invariably, students did not keep trying to convince their parents that it was a good idea!
The same idea applies to proofs…once you’ve proven the idea, stop! You’re done!
This helps students who don’t understand when they have finished with their proof. Did you get to the prove statement? Then you’re done!
Quick Assessments
Here’s a formative assessment that you can use with congruent triangles proofs. It has five questions, automatically graded using Google Forms. If you want to make one yourself, take a look at the preview for ideas on how to create it.
I hope that these ideas are helpful for you as you plan your proofs instruction.🙂
Go here for ideas on proving parallelograms!
You’ve got this!