How can I write an essay that analyzes the social or environmental factors at work in examples of juvenile delinquency in the newspaper?

To complete this assignment, your best strategy might be to choose a specific form of juvenile delinquency or cause of it as your focus so that you can narrow your search and write a coherent essay. In my experience of over 20 years of university teaching, the problem students are most likely to face with this sort of assignment is unfocused writing that simply summarizes seeming random results from a search engine. 
A good starting point might be looking at a recent study on juvenile offenders in Los Angeles. This study shows that over 30 percent of juvenile offenders are re-arrested within a year. It also finds that over 90 percent of juvenile offenders in the Los Angeles system have some sort of mental health issues. 
You could use this information to focus your essay on the prevalence of mental health issues among juvenile offenders in Los Angeles, using a internet search engine to do a Boolean search for three articles in the Los Angeles Times about individual cases of juvenile offenders, and for each case, show how mental health issues, substance abuse, and a chaotic home environment contributed to their criminal activities. To make the essay even more focused, you could restrict your search to one specific type of crime, such as violent crime or selling drugs.