Age gap?

hmmm.... if teacherxstudent is okay with you, maybe try hirunaka no ryuusei?

Ooooh oh oh this is my wheelhouse

Just a sec let me move to pc

I'm assuming older male...
http://www.mangago.zone/read-manga/faster_than_a_kiss/
http://www.mangago.zone/read-manga/love_so_life/
http://www.mangago.zone/read-manga/keishichou_tokuhanka_007/ one of the BEST manga...
http://www.mangago.zone/read-manga/v_b_rose/
http://www.mangago.zone/read-manga/sekai_de_ichiban_daikirai/
skip beat...obviously
http://www.mangago.zone/read-manga/kamisama_hajimemashita/ totally counts cause he's like several hundred years old :P
http://www.mangago.zone/read-manga/takane_to_hana/ awesome and funny
http://www.mangago.zone/read-manga/black_bird/ fantasy plot to this one as well
http://www.mangago.zone/read-manga/the_one/ one of the best manwa ever
http://www.mangago.zone/read-manga/kainushi_wa_akuma/ again pretty sure he's like technically WAY older...cause he's not human....also he's not human you've been warned ;)
http://www.mangago.zone/read-manga/dengeki_daisy/ awesome
http://www.mangago.zone/read-manga/mahou_tsukai_no_yome/ another freaking awesome one....again he's not human. But its still super cool
http://www.mangago.zone/read-manga/p_to_jk/ really enjoyed this :D
http://www.mangago.zone/read-manga/ultimate_venus/
http://www.mangago.zone/read-manga/taiyou_no_ie/ this is amazing the heroine is the cutest shoujo mc ever
http://www.mangago.zone/read-manga/ai_hime_ai_to_himegoto/ one of my favorite manga guys ever.
http://www.mangago.zone/read-manga/kinkyori_renai/ teacher student
http://www.mangago.zone/read-manga/anatolia_story/ awesome fantasy plot too...a classic
http://www.mangago.zone/read-manga/yumemiru_taiyou/
http://www.mangago.zone/read-manga/shiawase_kissa_sanchoume/
http://www.mangago.zone/read-manga/library_wars_love_war/ not finished but the aniime and movie finished the story I believe
http://www.mangago.zone/read-manga/ten_no_ryuu_chi_no_sakura/

Oh my god hirunaka no ryuusei made me cry so much
It makes my heart hurt, everytime she says sensei and looks at him i used to think i will cry rivers now
It is such a good manga totally check it out

1 of my fav themes! I have a little collection of my fav age-gap ones. Though it's not all the ones out there, just my personal fav ones. Check them out if you like -
http://www.mangago.zone/home/mangalist/53203/
The ones that have age-gap, are mentioned in the 1st pointer of review note. BUT it's STRICTLY Older Male x Younger Female Age-Gap. So, avoid this one if you are looking for Older Female x Younger Male ones.