In this quick activity, students use Geogebra and a self-checking Google Sheets page to explore whether or not any three combinations of side lengths will create a triangle. This activity lends itself well to self-discovery of the Triangle Side Length Theorem, which states that the sum of any two sides of a triangle must be greater than the length of the third side.

This resource, if shared with students via Google Classroom, works best with the "Make a copy for each student" option. It makes a fantastic quick warm up. You could also use the Google Form with some hand held manipulatives to physically build the triangles, too.