This is a great video to watch to get an idea about this unit.
To find the mean (or average) from a set of values, add all of the values together, then divide by the number of values given. This will get your mean (or average).
To find the median, there are two methods, depending on the number of values.
Odd Number of Values: Simply find the middle
Even Number of Values: Find the two middle values, add them together, then divide by two. That will give you your median.
The Mode is the value that repeats the most. Simply line the values up and determine which value repeats the most.