I love reading gender bender mangas!

I know the well known one are Ouren Host Club, Ranma 1/2, Sailor Moon Stars, annd Hana Kimi~

= my favorite
Click the title to read. 8)
Here are some other recommendations you should check:
After School Nightmare

QUOTE
Like most teenagers, Mashiro Ichijo has a secret. But Mashiro's secret is that he's neither fully male nor female! So far, Mashiro's been able to live his life as a boy, but all this changes when he's informed of a new class he must take in order to graduate from his elite prep school. To pass, he must find the Key, and the only way to find it is to enter into a nightmare world where his body and soul are put at the mercy of the worst kind of enemies--his classmates!
Pretty Face

QUOTE
Rando Masashi, a self-centered, brash karate star, was the victim of a horrific bus accident that left him comatose, his face terribly disfigured by extensive burns. Genius plastic surgeon Dr. Manabe saved Rando's life and went to work on his face, gradually reconstructing it based on a photograph found in the wreckage of the bus. When Rando wakes up from his coma, a year has passed, and Dr. Manabe has made remarkable progress. But in a cruel twist of fate, the photo that the doctor used as his reference was not a picture of Rando, but of Rina Kurimi, the girl whom Rando has a crush on!
^this manga made me LOLOLOL soo much
Girl Got Game/Power
QUOTE
Kyo Aizawa is very excited about getting to attend Seisyu Academy, which is famous for its adorable girls' uniforms. Her spirits are crushed, however, when she opens the package containing her school uniform to find a boy's uniform.
Her father explains to her that, as Seisyu Academy is also famous for its boys' basketball program, he enrolled her as a boy so she can fulfill his own dream of becoming an NBA basketball star. To make matters worse, she has to stay in the boys' dorms, and her roommate is the same boy she came to hate at tryouts.
Ingenuo
QUOTE
Ding Jiayu dreams of being a photographer. Her idol is none other than Yung Jo. When Yung Jo’s photography company holds an audition to find a new photographer, Jiayu decides to take a chance. The thing is, Yung Jo’s company doesn’t hire women, so Jiayu has no choice but to dress up as man and enter. Yung Jo takes great interest in Jiayu's talent and makes her his apprentice. It may seem like a dream to work with your idol, but for Jiayu, it's nothing of the sort. She takes a beating from Yung Jo everyday, and since all the crew members think she is a guy…
Mint na Bokura
QUOTE
Noeru has a close connection to his twin sister, Maria. When Noeru learns Maria's gone to a boarding school to be near her first love, he goes after her to stop it. The only problem is that the school has only one bed left, for a girl student. Disguised as a girl, Noeru attempts to bring his sister home. In the process, love is found, lost, and found again for both of them.
My Barbaric Girlfriend/Your and My Secret

QUOTE
Two teens see how the other half lives!
The girl: cute but obnoxious, pretty but violent, petite but rude.
The guy: shy and slender and secretly in love with the girl.
When her mad scientist grandfather accidentally switches their bodies--it's freaky Friday, Saturday, Sunday, and every day! Akira Uehara is mortified when his best buddy starts hitting on "him," and is embarrassed to look at "himself" in the mirror in her underwear! He can't wait to get back to being a boy. But Nanako Momoi has other ideas--she is starting to enjoy life in Akira's body!
W Juliet
QUOTE
Narita Makoto would like nothing more than to achieve his dream of becoming an actor, but his strict father decrees that Makoto is to inherit the family's dojo and will not be allowed to pursue his dream. Finaly, Makoto's father says that if Makoto can demonstrate his acting skills by getting through his last two years of highschool as a girl, he will be allowed to do whatever he wants. However, if anyone finds out, he must return home and bend to his father's will. Makoto agrees and leaves his current school to attend Sakuraga-Oka High School, where he joins the drama club and begins to live his life as a beautiful and enormously popular high school girl.
Nicoichi
QUOTE
This is a story about the love and hardships of a 29-year old guy named Makoto Suda. Makoto is an ordinary office worker in every sense but one: in front of Takashi, his stepchild, he has disguised himself as a woman and played the role of a beautiful mother. Leading this life of a “fatherless family”, for some reason he falls in love with a woman. One morning he happens to see her on a crowded train but…
Cheeky Angel
QUOTE
Megumi Amatsuka, a rough and tumble nine-year-old boy, always dreamt of becoming the "manliest man on earth." Upon receiving a book of magic from a sorcerer whom he saved from a group of local thugs, Megumi summons a genie in order to make a wish. But due to a sick twist of fate, the genie turns out to be an evil one, and Megumi winds up being the "womanliest woman on earth"! Six years later...Megumi is the most desirable girl in school, but deep within her hot-mama façade is the same trash-talkin', punk-stompin' boy.
Penguin Revolution
QUOTE
High school student Yukari Fujimaru knows a potential star when she sees one because she sees the special "aura" they give off, in the form of angelic wings. Yukari's fellow student, the beautiful and responsible student body vice president, Ryoko Katsuragi, has a small pair of wings herself, and is one of these aspiring talents. She's so talented, in fact, that no one even knows that "she" is actually a boy in disguise. Due to a series of events, Yukari has come to discover Ryoko, or rather, Ryou's secret, and is hired as a manager for Ryou by the president of the Peacock Talent Agency. Living together with the promising Ryou and his rather dashing room mate, Makoto Ayori, the number one star in Peacock who is also the lazy, ruffle-headed student body president, is bound to be an adventure! Now, to make her own down-to-earth dream come true Yukari must help her new friend become a star while doing her best to protect both her beloved room mates.
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Any other suggestions