Explore Ratios and Proportions with Racing Barriers. The Max Speed Racing Circuit is one of the best-known stock car racing circuits in the world. In this story task, you will get to design your own race car utilizing scale factor, analyze all types of racing statistics, make an argument to determine who is the greatest driver of all time in the Max Speed Racing Circuit, and much more! You will also meet Rocky Ray Johnson and Jessica Chestnut. Rocky Ray and Jessica broke through the barrier becoming the first African-American and first female driver to join the Max Speed Racing Circuit!