So many. Here's one. It has a sequel as well.
"Ai wo Utau yori Ore ni Oborero!"
Dude. This is the ask I've been waiting my whole otaku life for. I haven't read much shoujo since discovering yaoi though, so these might be a bit old. (In no particular order)
1. Kaichou wa Maid Sama
2. Beauty Pop
3. Special A
4. Seiyuu-ka
5. Ouran High School Host Club
5. Charming Junkie
6. Fruits Basket
7. Kyou, Koi wo Hajimemasu
8. Cat Street
9. Fly High!
10. Last Game
11. High School Debut
12. Gakuen Alice
13. Yumeiro Pattissiere
14. Akatsuki no Yona (not completed, but I had to mention it because it's so amazing)
Well, hopefully this list keeps you going for some time. I know several of them are pretty mainstream, so you've probably read them already.
And all works of Sakisaka Io sensei like Ao haru ride, Blue, Mascara blue.
Lovely Complex ٩(๑❛ᴗ❛๑)۶
these are the good ones. (๑•ㅂ•)و✧
Well, I only wanted to recommend one or two but it pissed me off how ppl only recommended ones with anime!
lemme just give you my top list
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NOTE: those with hearts are a must read and i really adore them the most but the others are really good too!
1- Horimiya "ongoing but have 80+ chaps"
(really unique plot-comedy-school life)
2-Last Game "completed 56 chaps"
(feels trips-perfect couple-my fav in comedy after lovely complex)
3-Hibi Chouchou "ongoing but have 75+ chaps"
(seems to be cliche plot but when you read it you won't be able to stop reading i read it over 5 times and I still blush and giggle at their adorableness!)
4-Hirunaka No Ryuusei "completed 78 chaps"
(THE MOST SATISFYING MANGA THAT WON A REWARD IN MY HEART FOR ITS ENDING!!! ITS A MUST!!!!)
5-Hiyokoi "completed"
(ADORABLE LITTLE THING!!! I JUST LOVE THIS ONE SO MUCH cuz its just so adorable you'll understand if you read it >//-//<) ah but i think it had an ova or something? idk
6- Tonari No Kaibutsu-kun "completed and have anime"
(but read the manga it have lot after the anime and it is worth it!)
7-Dengeki Daisy "completed"
(I really liked this one was deep and the plot was meh but I enjoyed it, it is a bit slow but again it is enjoyable)
8- Beast Master "completed"
(cliche but worth it, I really liked how the couple in this got together and how they act is so funny xD)
9-Pika Ichi "ongoing 27+ chaps"
(this really is good but it's ongoing and T^T they not a couple in it but THEY SHOULD BE!!! but it is awesome enough to read!)
10-Yumemiru Taiyou "completed"
(sweet slice of life shoujo manga that give you the feels it is absolutely a good read!)
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Hirunaka no Ryuusei
http://www.mangago.me/read-manga/hirunaka_no_ryuusei/
(๑•ㅂ•)و✧
WOW! Everyone is SO SWEET!! They recommended all the nice & cute ones. So let me be the bad one & start with something different -
~Bitter Virgin - http://www.mangago.me/read-manga/bitter_virgin/
One of My Ultimate Favs! It's such a versatile shoujo! I couldn't just not love it! If u like unique shoujos that deviate from stereotypical ones then u may like this one.
~Orange - http://www.mangago.me/read-manga/orange_takano_ichigo/
I can not describe in mere words just HOW MUCH I LOVE this story! It's just PERFECT! Highly recommended.
~Kon no Ki Konoha - http://www.mangago.me/read-manga/kon_no_ki_konoha/
My fav shoujo oneshot.
~ Ai Hime Ai To Himegoto - http://www.mangago.me/read-manga/ai_hime_ai_to_himegoto/
One of my very first shoujo mangas. But I still love to re-read this one to this date.
~ Help!! - http://www.mangago.me/read-manga/help/
I have a HUGE thing for teacher-student shoujos. And this is by far my fav one. The romance is PAINFULLY SLOW to almost NON-EXISTENT but it still tugs at my heart strings.
in a shoujo mood today. not looking for anything specific, just tell me your favorite shoujo manga and i'll check it out. i would prefer that it be completed and not ongoing, though. thanks in advance ٩(๑❛ᴗ❛๑)۶