First, order up the numbers into order:
2, 3, 3, 5, 6, 8
Next, cut off the ones on each side to get the median.
2, 3, 3, 5, 6, 8
2, 3, 3, 5, 6, 8
Now with this, add the two middle numbers and divide by 2 to find the avg. of them:
3+5 = 8
8/2 = 4 is the Median
Next, split up the number list into the lower section and the higher section, now knowing the Median:
2, 3, 3 Lower
5, 6, 8 Higher
Then, find the Median of each of these sections.
2, 3, 3 Lower Quartile is 3
5, 6, 8 Higher Quartile is 6
Hope that helps.