Steps for creating Box Plots:
Step 1: Order the data set values in order from least to greatest
Step 2: Find the median of all data values
Step 3: Create a number line that includes all values from your data set
Step 4: Plot your lowest and highest values along with the median above the number line
Step 5: Find the median of the lower half of the data set and plot it
Step 6: Find the median of the upper half of your data set and plot it
Step 7: Draw a box around the medians of the lower half and upper half. It will also contain the median of the entire data set
Step 8: Draw a line from the lower half media to the lowest value of your data set
Step 9: Draw a line from the upper half median to the highest value in your data set (whiskers)
To find the Range of your data set you subtract your lowest value from the highest value
To find the Interquartile Range (IQR) you subtract the median value from the lower half of your data set from the median of the upper half of your data set.