I'm 28 and went into this movie knowing full well it's aimed at teenagers. I enjoy fluffy teen romance though so have no problem with cheesy storylines and characters, and this film is full of them! What I did have a problem with is the way relationships between women and men are portrayed in this film. It seems to start out ok: the leading teenage girl (Elle) has a male best friend (Lee) and their relationship is pretty cute and I thought it was quite progressive to show a girl and a boy who really are just friends without all the usual sexual tension you get in movies like this. Lee has an older brother (Noah) who is unremarkable except he is very good looking.
Things then start to go a bit wrong. It turns out Noah is pretty controlling of Elle, even telling all the other boys at school they can't date her or he'll hurt them. He frequently gets into fights with other boys when he sees them talking to her and beats people up. In one scene he's shouting at Elle to get in his car and even slams his fists down on the car bonnet aggressively whilst telling her, which made me feel really uncomfortable. There's even one scene where Elle has a minor accident and cuts her face, and Lee asks her if Noah hit her! That scene is then never followed up by any explanation - why would Lee immediately assume Noah beat up Elle?!
Meanwhile, Lee, who is portrayed as Elle's loveable and affable best friend controls her in his own way, by freaking out when he finds out she's dating Noah, asking her if she's having sex with him (none of his business?) and only accepting her back as a friend when she is no longer seeing Noah, despite her being obviously devastated about breaking up with him. In one scene he insists to her that breaking up with him was the right decision (he didn't really leave her any choice though did he).
There are also a couple of weird scenes where Elle strips off to the delight of crowds of boys, once when she was so drunk she had no idea what she was doing and everyone just stood there and allowed her to take her dress off. Another time in the boys locker room. Both scenes were odd and again, made me feel uncomfortable.
Other strange elements of the film are Noah being portrayed as a bad boy who gets into fights all the time, yet the reasons for this are not even explored one tiny bit. And even weirder, despite him being a bad boy who is presumably troubled, it's revealed that he's really randomly got a place at Harvard. This was weird because at no point during the film was it suggested that he was academic or even remotely ambitious, yet you don't get into Harvard without trying! There's also a summer montage of Elle and Noah together which is basically them having sex anywhere and everywhere. It felt a little yucky because she's a high school teenager and I thought it was an irresponsible message to send teenage girls out there.
A really funny part is when the kissing booth is immortalised at their prom as a memory that touched everybody's lives and Elle's all emotional because she was "part of something". REALLY? A kissing booth?!
Then, after sitting through all of this, Noah goes off to Harvard at the end of the movie and you're very much left with the impression that's the end of their romance. So I didn't even get the feel-good happy ending I was after.
So basically, this movie is really awful and if you have a daughter, I'd actually advise extreme caution allowing young girls to watch this movie because it really does send out the wrong messages about relationships and sex.