Extra point or 2-point conversion - Updated

In 2015 the NFL changed the extra point kick distance to 33 yards and now teams have a tough decision to make, go for one or two points?  The one point extra point is no longer a given with a success rate of about 95%.  Teams can go for two by trying to get the ball in the end zone from the two yard line. Teams have been successful at two-point conversions in the past about 50% of the time, but early in the 2018 season the success rate has shot up over 60%!   So we ask students, which does it make more sense to do?  Given the data, should teams go for one or two points?  Which do you expect will pay off with more points over the long run?  See this interesting article on the Steelers and their 2-point conversion strategy.  Or this article from the538 about more teams going for it then ever. 

Give students a chance to individually think through the problem, then work in small groups as they come up with their own way of thinking about the problem.  Students may come up on their own with the number of points expected over time (expected value), if not, you can always push their thinking in this way or toward some other productive strategy.  Maybe students estimate the outcomes for extra points and two point conversions over ten trials attempts for each, then 20, maybe 100.  Can they tell how many points would be expected over 100 attempts for each?  They are then finding expected value!

Finally, students consider how they could change the point value of the two-point conversion or change the line of scrimmage of either play to make the expected value of both plays nearly equal.