You Are Teaching the Times Tables to Your Class

You are teaching the times tables to your class.Today you plan to give a timed test of the multiplication math facts.Your goal is to promote intrinsic motivation.Given what we know about intrinsic motivation, which one of the following strategies should be most effective?

A) Tell students that you expect them to get a certain number of items correct.
B) Promise five minutes of free time to students who get a certain number of items correct.
C) Encourage students to see if they can do better on the test than they did last time.
D) Put a shiny gold star on every perfect test paper.