https://youtu.be/4NqQ7dky_Uw My favorite is in this utube video list!
Here some completed ones
http://www.mangago.zone/read-manga/back_to_the_highteen/
http://www.mangago.zone/read-manga/oh_lord_jesus/
http://www.mangago.zone/read-manga/quoth_the_boy/
http://www.mangago.zone/read-manga/secret_crush/
http://www.mangago.zone/read-manga/love_is_a_cherry_color/
http://www.mangago.zone/read-manga/july_found_by_chance/
http://www.mangago.zone/read-manga/forever_mine/
http://www.mangago.zone/read-manga/vitamin_c_vitamin_d/
http://www.mangago.zone/read-manga/orange_marmalade/
http://www.mangago.zone/read-manga/love_doesnt_talk/
http://www.mangago.zone/read-manga/gradually_close_to_the_heart/
http://www.mangago.zone/read-manga/mango_s_bone/h
ttp://www.mangago.zone/read-manga/evergreen_tea_shop/
http://www.mangago.zone/read-manga/scorching_romance/
Also here some more straight romance webtoons (random plots, completed ones)
http://www.mangago.zone/home/mangalist/685444/?filter=&page=1
I'm looking for wentoon about boy x girl. I want it to be a story set at school.