Goal: understand slope conceptually and calculate slope through any two points.
How do you plan to make the ratio of rise to run hands on and visual for students? How about by asking them to create zip lines? In this activity students will work in teams to create fast and slow zip lines using fishing line, paper clips, and any toy you can hang from the clip. Students will experiment with the ratio of rise to run as they must use the entire piece of wire for every zip line run meaning the only changes that are allowed are rise and run.
Bring the ratio discussion around to percent grade and tangent ratios in geometry if you feel your students are ready for outside connections - questions for these are at the end of the activity.
This lesson leads to a great closing discussion about the slope of horizontal lines (slope of 0 as the rider would move zero feet on this line) and of vertical lines (undefined slope as the rider would not slide but free fall instead). So many great visuals that I encourage taking pictures throughout the lesson for later reference.