I had read in 1984 in English classes and I was thrilled. Luckily I purchased this edition of the novel, because here you can find next to short summaries of each chapter (in English of course) also Character Notes to the different characters. This is very handy if you times not quite understand a chapter (or not quite prepared for the classroom) has.
Also you can find here English-English explanations of difficult words and even George Orwell's life is briefly presented chronologically, besides the political rule events at that time are listed.
All in all a more than recommendable book, especially for high school students.