Desmos: a free online graphing calculator. www.desmos.com/calculator Desmos - Marbleslides Activities: allows for students to explore connections between the graphs and equations of lines, parabolas, and more. teacher.desmos.com/search?q=marbleslides Desmos - Polygraph Activities: students are paired up and one student picks the graph and answers questions, the other student asks the questions and tries to identify the chosen graph. Both students see the need for more precise vocabulary. teacher.desmos.com/search?q=polygraph