This Headline Story helps to introduce probability to your students.
Each day, 5 students put their names in a bag. One name is selected at random to take attendance. So far this week, a girl was chosen every day. Today is Friday and 3 girls and 2 boys put their names into the bag. Is a boy or a girl more likely to be chosen today?
Students might expect that because girls have been picked for so many days, it’s not likely to happen again, or they might think that this week must be girls’ week and so a girl will be picked again. But, since there is no reason to think that any one student is more likely to be picked than any other, and because there are more girls’ than boys’ names in the bag, it is actually more likely that a girl will be picked.