Anything by Asimov is good, but some are probably a bit esoteric for a beginning reader. Heinlein is probably the classic. Starship Troopers was supposedly required reading at the Naval Academy at one point. I would point them at some anthologies, the ones that Asimov edited where really good, providing history and background to go with the stories.
Don't forget Jack Chalker. Chalker writes on a level easily deciphered by young adults, and offers pure escapism in his novels.
If not Heinlein or Asimov, everyone should read Ray Bradbury. Bradbury is on of the foundational writers of science fiction. The world's loss of Mr. Bradbury in 2012 was a tragedy. His legacy will live forever though. His novels and short stories span every level of reading ability, and no one will ever waste time reading anything he crafted. Look for Dandelion Wine, Something Wicked This Way Comes, The Illustrated Man, The October Country, The Martian Chronicles, R is for Rocket, I Sing the Body Electric, and hundreds of other titles.
Don't forget Harlan Ellison or H.P. Lovecraft, but be wary that many of their stories can be either disturbing or contain higher level content.
Arthur C. Clarke is another hugely important science fiction writer. Mr. Clarke's knowledge was critical to the development of the NASA programs and he consulted for decade on the space programs of many nations. One of Clarke's greatest legacies was the novel Childhood's End. A bit dark, it deals with issues of first contact, paranoia, utopia/dystopia, and the transformation of the entire human race.
Compulsive Reader's Suggestions:Here are some scifi writers who have written some great Young Adult books:I would like to add Alan Dean Foster to this list. As a teen, I read many of his novels and each time was swept away into the story. Mr. Foster has a unique way of telling a story that just draws you into the worlds he creates with vivid detail. My favorites were the Star Trek Log Books, and one of the first non-Lucas Star Wars novels, Splinter of the Minds Eye. Consider reading one of his best novels, Nor Crystal Tears.
But my favorite one of all are the Flinx and Pip novels.
Novels featuring Flinx (aka Philip Lynx)I've read all these several times, and they still are thrilling to read.
I highly recommend them!
The beauty of the science fiction genre, that has not been touched on here, is that every other genre can neatly fit within it. Every story can be told from a SciFi perspective, be it western, romance, mystery, thriller, or any other type of writing.
Here's a hint for finding good science fiction and fantasy:
While most of the cover art of these two genres get panned often as cheesy or baudy, some of the best novels are covered by the same artists. Look for stories you like to read, then check on the copyright page for the artist who drew the cover. Chances are you will see names like Michael Whelan, Rowena (Morrill), Donna Diamond, and H.R. Van Dongen (a classic pulp cover artist), as well as many others. Look for these artists and the story under the cover is likely to be a good one.
You can find lists of supernatural or romance books by visiting wattpad.com/stories/paranormal/romance
Some good books for teens with romance, humor, and supernatural elements featuring possessive boyfriends include "Twilight" by Stephenie Meyer, "Hush, Hush" by Becca Fitzpatrick, and "The Mortal Instruments" series by Cassandra Clare. These books blend romance, mystery, and fantasy in a compelling way that will keep readers hooked.
Some good books currently recommended to teens are Maze Runner, Twilight, Beautiful Creatures and Harry Potter.
-I recommend "Xoe" by Sara C. Roethle.
Obernewten chronicles
Haunted Illinois, Haunted Chicago and Mysterious Illinois are some of the good books about supernatural things and spirited ghosts.
The Twilight series, Ready or Not, and the Private series.
The Christy Miller series. It goes by volumes. 3 books per {book} volume.
-I recommend "Xoe" by Sara C. Roethle.
Today most books that I read have some sort of supernatural creature but there are some that don't. I enjoy books that are written in first person and if you also do than you might like some of the Dear Canada books. Besides that I'm not too sure of any other books because right now most authors are writing about supernatural creatures because that is what the public is demanding. Don't know how much I helped but maybe you'll read some vampire books, their really good.
"There are several highly rated Christian Romance novels available. The authors of some of these are JoAnn Durgin, Dee Henderson, Linda Windsor, Sharon Gillenwater, and Erin Rainwater."
Some good classical drama slash romance books for adults include "Pride and Prejudice" by Jane Austen, "Romeo and Juliet" by William Shakespeare, "Anna Karenina" by Leo Tolstoy, and "Wuthering Heights" by Emily Brontë. These books combine elements of drama and romance in a timeless way that continues to resonate with readers.