 If you liked
Tora Kiss: A School Odyssey
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 ...then you might like
Rakudai Kishi no Cavalry
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Both these manga occurs in school, as well having a rank system where both protagonist are the lowest scoring student and everyone believe they're weak and pathetic.
That is until they see their match, where both of them are quite powerful.
If you enjoy manga where the protagonist has hidden talent and are proclaim as weaklings but are actually strong, you'll love these both.