Read this in the school library - all the stories were very dysotopian. One involved a character named 'Emelen' who by the end of the story discovers they are just one of many discarded clones (MLN). Another told the story of a boy and his science fair project involving cereal where he determined that the ruling government (which was a corporation who owned all of the US) was adding a drug to dumb down the populace.
This is a long shot, but could it be The Other Side of Tomorrow, edited by Roger Elwood. For some reason I associate the name Emelen with this anthology. I thought I had a copy but after a brief search I can't find it, and a quick Google doesn't help much. The only thing is that I don't remember "A Pail of Air" being in the book.