Episodes 4-5 are stronger, but episodes 1-3 are actually quite fun. As usual, there's violence, heads being bitten off, etc., but also lighter material and outright comedy. Ilse's Notebook gets intense, but even that episode made me laugh with Hange's Titan love. Yes, she loves Titans. That's "love" in the sense of "wants to immobilise and dissect one while it's still alive", but she's getting so excited about being a mad scientist that you could devise fan theories about other possibilities. She actually chases one, while the poor thing's just trying to get away.

All five of these episodes happen during the five-year gap between ep.2 and ep.3 of Season 1. Wall Maria has fallen and the battle of Trost is coming. Eren, Armin and Mikasa are in the 104th Training Corps.

Unlike most of these OVAs, this episode actually has a Titan in it. Hanji sees the poor thing and wants it. This made me laugh... but then we find the notebook and corpse of Ilse Langnar. The episode gets dark and, ultimately, remarkable. I really liked this one.

Good grief, Jean's a grumpy knob. When his mother comes to visit, he's like a moody teenager. (Admittedly, though, it might be embarrassing to have your mother visit the military barracks and call you by a childhood name in front of your fellow trainees.) Jean then gets into an argument with Potato Girl (i.e. Sasha). Commander Pyxis (who's drunk) orders that their fight be resolved with a cook-off. If you've ever wanted to see Attack on Titan as a stupid cooking anime, watch this episode. Pyxis also outdoes Shokugeki no Souma for an over-the-top foodgasm.

This is silly and funny.

A more straightforward episode. The 104th Cadet Corps are on a training exercise, in the wilds on their own. Hurrah, no Titans! Whoops, bandits.

This is a two-part adaptation of a game/manga spin-off. It's quite strong, but it suffers more than usual from the curse of foreknowledge. I watched it several years after its release and it's very, very obvious who'll live and die... but what the hell. It's a prequel, in a famously death-ridden franchise. It stars Captain Levi before he joined the Survey Corps, plus some friends of his we've never met before. No prizes for guessing who survives.

Chronologically, I think these are the show's first episodes. (Bar of course all the Season 4 backstory.) Series 1 starts in year 845, whereas this is still year 844. Wall Maria hasn't yet fallen and Levi's living in the rarely-seen underground city to which citizens will be evacuated during the Uprising arc. (That was cool. You'd expect subterranean life to be the perfect solution to the Titan problem, but unfortunately it has health costs for its inhabitants and it's not self-sufficient. It depends on the outside world for food and more.)

It's quite a strong pair of episodes and it strengthened my emotional connection to Levi. I wouldn't go so far as to say I care about that rude, psychotic fan-favourite, but watching this might make him less boring in other episodes. He also gets a worrying knife scene.

For a franchise watching order, I'd suggest...

Junior High is a non-canonical parody and for the love of sanity avoid the live-action adaptations, i.e. Counter Rockets and the two silly movies. I quite like that watching order. It fleshes out the five-year timeskip between ep.2 and ep.3 in the original show and gives us more context on key characters. Also, importantly, I enjoyed these OVAs. They're all filler episodes, mind you, released as bonus Blu-rays packaged with special editions of the manga. You don't need to watch them, but they're quite fun and often lighter than usual for Attack on Titan.