Definitely the weakest episode of Class I've encountered so far, and by a pretty wide margin, and even then, it's not that bad.  I just haven't connected to April's character like I have the other main characters, and the whole story with Corakinus and the shadow aliens just wasn't that compelling to me.  It seems like all the other main characters have a specific role and something that had me hooked with the first few episodes, and April is kind of coming across as the odd one out for me.  She's not bad, but it isn't quite the same level of engaging as the others.  The whole alien flower side story also didn't offer much, in my opinion, either.