Variation in sample size for coin tosses
You can download an Excel spreadsheet that simulates a coin tossing activity.
It contains 6 sheets. The first sheet produces 10 random tosses of a coin and reports the number and percentage of heads and tails. The second sheet does this for 50 tosses, the third for 100 tosses, the fourth for 500 tosses and the fifth for 1000 tosses. The sixth sheet contains all of the results.
Students record the percentage of heads on a number line for twenty repeats of 10 random tosses of a coin.
Then they record on a separate number line (with the same scale) the percentages of heads for twenty repeats of the increasing number of trials (50, 100, 500 and 1000).
They should observe that the variation of the percentage of heads from 50% decreases as the number of trials increases.