I'm looking for a manga where the female character is secretly awesome but knowingly hides it for whatever reason.
Kind of like the male lead character in Horimiya but a girl. Or Yankumi in Gokusen.
Or Warau Kanoko-sama series because awesome doesn't have to mean fighting skills.

I'm not looking for a Cinderella-type transformation story, where the geeky girl turns out to be secretly beautiful (although those stories are fun too ^_^) but ones where the girl is already awesome/confident/a super nice person/or whatever, but just chooses not to display it/isn't obvious to other people.

you can try ;

1/2 Prince
ENT.
Junai Tokkou Taichou!
Keishichou Tokuhanka 007
Obaka-chan, Koigatariki
Oresama Teacher - definitely cool
Pika Ichi - amazing male & female lead
Seiyuu Ka-!
Yanki-kun to Megane-chan
Zerozaki Soushiki no Ningen Shiken

Gotta second:

You could also try Change 2! and Zero In

Arigatou HOWEVER, it is incredibly bleak with buttloads of dark humor, borders on dead baby humor, in the latter half. Somehow the main female protagonist, and her family ends up all right. I think she may even be one of my all time favorite characters in manga.

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Sarcasm just doesn't work over the internet.

Saver- Though she doesn't entirely hide it...

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Nulla in mundo pax sincera
"Always go too far, because that's where you'll find the truth." - Albert Camus

9 Banme no Musashi

I second
Oresama Teacher
Yanki-kun to Megane-chan

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I third Oresama Teacher and Yanki-kun to Megane-chan

alsooo...
my fav manga of ALL TIMES... Superior - she hides the fact that she's actually a demon lord~

Red Lion .. also my fav~ where she hides that she's actually the famous 'red lion' fighter

Kimi ga Uso o Tsuita the manga is too about hidden personality...BUT... the one i'm talkin about is the first SIDE STORY.. it's called 'Ultimate Boyfriend and Addicted Girlfriend' where the girl hides she's an ex-yankee

Beauty Pop - she hides she's an AWESOME hairdresser (or whatever u call it xD)

Arisa .. i dunno about this one... it's actually about a twin going as the other twin...but the twin that's going as the other twin is really awesome and good at fighting

Otokomae! Beads Kurabu about a girl who tries to hide her... 'manly' side

I have many more... but i think this will be enough for one time?
I hope i helped... AND if u actually want more, send me a message ;3





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Find me on DeviantArt *w*
http://xkocicax.deviantart.com/

Only two I can think of are Change 123 and Zero In.

Nononono- cos she's doing a males sport and beats most of them at it but no one knows that she's a girl, so if they knew it-it would show she was awesome

Othello-Has a split personality, so she's weak willed but her awesome side comes out sometimes

Fall in love like a comic-hides the fact she's a well known manga-ka

Pig bride-hides her face behind a mask

Superior-Hides that shes a demon

Love in the mask-gender bender type where shes hiding shes a girl, and does dangerous bodyguard and mafia work.

I second otokomae, red lion, and beauty pop.

Siesta maybe