Set the radius slider to a value of your choice, from 50 to 175 units of length. Click on the green flag. This project draws the length of arc of a circle equal in length to the radius of the circle. Starting from the center C, the project draws the radius (color = red ) set in the slider. The arc that subtends the angle = 57.2957º = 1 radian, is then drawn in red. The sprite is moved to (0, 0), turned to the right, turned left through 57.2957º, and then moved a length equal to the radius to arrive at the end of the arc. The 'arc steps', as reported in the window, equal the length of the radius. Test several radii.
In Bloom's Taxonomy of Educational Objectives, a test of a learner's 'comprehension' of a concept is the ability of the learner to 'rephrase or restate' the concept. In this project, the 'radian' concept is stated and expressed in the form of a Scratch project. I think one would have to agree that the ability to write such a project would require that the coder 'understands' the radian concept. Coding as 'a test of 'comprehension' is just one reason I believe learning to code is important. Other projects in the series: Perpendicular Mouse https://scratch.mit.edu/projects/20186064/ Parallel Mouse https://scratch.mit.edu/projects/21653980 Angle Mouse https://scratch.mit.edu/projects/16793255/
