>>4434706
My go-to rec is 聖クロス女学院物語. It's a kids book so it's much easier to read than your average LN, and although it starts off slow and is axed after just three volumes (with the fourth half-finished on the author's blog), by the 2-3rd volume it has enough gay tension everywhere. Essentially it's about a mystery-solving club in a Marimite-like school, but the protagonists spend more time being silly and admiring their upperclassmen than actually solving mysteries, at least until things start getting weird.
Really a shame that it never continued, the fourth volume with the school play was getting intense.