Too much Cameron Diaz.
Not enough Jason Segel.
After saying that, there isn’t a lot left to say. Bad Teacher isn’t nearly as funny as it would have been if Jason Segel and Cameron Diaz at least shared the screen 50/50. Instead, we get Cameron Diaz as the single main character and Jason Segel with a much more minor role. Hell, Lucy Punch spent the second most amount of time on the screen after Diaz. I’m not complaining about that, I like her, but Jason Segel was completely underutilized. The fact is, Bad Teacher has more than enough talent at its disposal to make for a good movie, but wastes all its time on Cameron Diaz. This is so problematic, it’s not even funny.
Actors aside, Bad Teacher could have also benefited from having more likable characters. I’m pretty sure the only likable character was Jason Segel’s. Justin Timberlake’s and Lucy Punch’s characters are only marginally more likable than Cameron Diaz’s completely awful character. What’s worse, is that while Justin Timberlake and Lucy Punch play characters that are unlikable in a way that works positively for the film, Cameron Diaz’s character just plain sucked all around.
With unlikable characters and focus on the wrong actors, you’d at least hope for a solid script, but holding out for such a thing will just yield disappointment. The film had potential, but it went unfulfilled. There was weren’t jokes where there needed to be and most of the ones that were there fell flat.
Bad Teacher isn’t an entire loss, it does have a few moments, but only so much as to be worth streaming from Netflix. I wouldn’t bother even wasting a DVD rental on it.