Investigating slope with Legos - Part 1

By Susan LoFranco on Apr 24, 2017

  • Graph a simple ratio by connecting the origin to a point representing the ratio in the form of y/x

This lesson will be in two parts - one investigating slope by building lego staircases and determining the slope and then by using two different sized triangles to understanding the proportional relationship.


  • Graph paper either raised or bold lined
  • Markers, dots, and/or tape to mark coordinates and lines on graph paper
  • Legos 
  • Large Print or Braille Ruler



  • Review vocabulary with student: y intercept, x and y coordinates, slope, right triangle, y intercept, rise and run
  • Review with the student the formula for slope y = mx+b: y = y coordinate, m = slope, x = x coordinate, b = y intercept   
  • Brainstorm with student real life examples of slope.  Some examples might be a roof, accessible ramps, ski slope, highway.  If you have examples around your school building create a scavenger hunt.  (Examples could include staircases, ramps in the building, seesaws, ramps used in science class, slides.)
  • Next the student will build a scaled staircase with Legos.  Each riser should be the same size.
  • The student should build several different staircases.  By building them different sizes and making some steep while others are more shallow the student should be able to notice that the slope is different. NOTE: This must be a proportional relationship rise to run, e.g. 1 up, 2 across.  
  • The student will be able to confirm that the slope is different in each staircase by plotting them both onto graph paper and solving for slope.  
  • With the student, identify the length and height of the staircase, plot the points on graph paper, and connect the points making a triangle.  Again the staircase must be plotted using the same proportional relationship used for creating the staircase.  Draw the the slope line so that it travels through the Y Axis.  This will become the Y intercept. (See y = mx+b example)
  • Together with the student choose one set of coordinates along the slope line and using the formula y = mx+b solve for the slope.  Use the media of student choice.
  • Provided the student understands how to solve for slope, have the student choose one more set of coordinates along the slope line and using the formula y = mx+b solve for slope independently.  The slope should be the same as it was for the first set of coordinates.  
  • Save all work to use in the second part of this lesson.  

slope collage


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