This year, I'm trying something new with my students. The idea came from a Desmos Fellow name Sean Sweeney. His blog post does a great job explaining how this works; I invite you to read about his experiences with what he calls his Marbleslides Challenge Set.
Two weeks ago, my geometry classes had just finished our unit on parallel and perpendicular lines. As part of that unit, I had students do the Desmos Marbleslides: Lines activity. Students loved the activity and asked for more Marbleslides. In response, I unleashed the challenge set to my students. [At least the first three challenges.]
Each week I am unlocking one more challenge inside the activity. This past week was an especially cool challenge, with the screen almost like a Plinko board. I've had a number students find solutions and experiences the "Success!" found at the end of the Desmos rainbow. And as a teacher, you know you're winning when students are begging for the next challenge to be unlocked.
I challenge you to read Sean's post and try the Desmos Marbleslides challenge out in your school. Happy 'Slidin'!