I alway like to start out my probability unit out with some hands on activities.
One of the first things we do is flip a coin. We talk about theoretical probability and how it should be 50% heads and 50% tails. They then toss the coin 10 times and record the outcomes. Most of time they get something other than 50/50. I then have them flip the coin 40 more times and add that to their original numbers. This should bring them closer to the 50/50 outcome. We then add the outcomes of all the students in the class and we are usually pretty close to matching the theoretical probability of 50/50. I make them calculate the experimental probability as a fraction, decimal and percent (great practice of this skill!)
Next, we toss a die. We go through the same process as the coin, but I usually have them toss the die in multiples of six.
We then move on to pulling counters from a tub. We again use the same process. They all have different amounts of tiles, so they all had to calculate their theoretical probability as well as their experimental probability after they pulled the tiles.