Here is a first day activity that I heard from Ann Watkins.
Get a packet of m&m's for every student. Have them eat it keeping track of how many brown candies there are. On a board number a line from zero to what ever is necessary and have each kid come up and put a postit note above the number that represents the number of brown candies in their packet. As the kids stick the paper one on top of the other, they are creating a very nice, normally distributed bar graph. You can then talk about the mean, median, mode, range, etc,etc.