Girl of the House and I read King Lear by William Shakespeare as part of her school studies, though we both consider reading Shakespeare more fun than work. King Lear is one of Shakespeare's greatest masterpieces and that's really saying something! Shakespeare's deep understanding of human nature combined with his complete mastery of the English language means he deserves the title of the greatest writer in the English-speaking world. Shakespeare is the literary equivalent of Bach and Mozart. Of all composers, those two give to their music a profound sense of rightness, of every note being exactly the right one, placed exactly in the right place, held for exactly the right duration, and performed by the exactly right instrument or voice. Their music has a sense of perfection~of there being nothing upon which to improve~that no other composers, great though they undoubtedly are, possess. What Bach and Mozart are to music, Shakespeare is to writing. His word choices, rhythms, cadences, and flow are perfect.
As for King Lear specifically, I don't know what I can say that has not already been said by better minds than mine. So let me talk about the edition we used from the Oxford School Shakespeare series. I'm not very familiar with the various editions of Shakespeare out there, but we have used the Oxford series consistently and have found it very helpful. There is plenty of history and background information provided, along with discussion and essay questions, plot summaries, lists of characters, project ideas, and explanatory annotations within the text of the play itself. A homeschooling mother who is not very confident that she can tackle Shakespeare or a student who just wants to learn on his own will be aided by the many helps provided. Though a small point, Girl of the House and I enjoy the cover pictures because we often recognize the actors! Our Henry V and Hamlet feature Kenneth Branagh, for instance, and our Taming of the Shrew features Vanessa Redgrave and Timothy Dalton. You can get copies from this series on Amazon for 1 penny plus shipping. With the Oxford School Shakespeare series, there is no excuse for not reading Shakespeare!