There were a number of incidents in my life when I observed stratification. First when I got into university there was stratification on the basis of region. Students from specific areas tend to stick together and stood up for each other. On the other hand when I joined an organization after my studies, People from same income class tend to stick together. They looked down upon the lower income groups. Work was effected in both the cases. As in both university and office one needs to work as a team. This could not be accomplished due to stratification.
Yes, I was a fat clumsy unpopular kid, way down on the scale of popularity. Once I wrote a poem for a lazy but popular girl, it was a trite 10 minute poem. The teacher raved about it. Meanwhile my own hard poem, was completely ignored. I held the coats at recess, and was generally ignored by teachers who were as impressed by popularity as anyone.