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15 year-old know it all son

308 replies

Spiritedlight · 24/02/2026 10:00

Hi everyone

I would like to have thoughts on how to handle/progress with son. He's 15, smart, lovely, very opinionated, completely resistant to being told anything and thinks he knows it all.

For example, a discussion about astrology/space etc - whilst DH is very knowledgable, DS will disagree with everything DH says, and quote, frankly, bollocks a lot of the time.

If we talk to him about the school's recommendations for self-study in Year 10 - which I know he's not doing, because I know what they expect - e.g., 2 x 30 mins of going over triple science lessons a week -he will completely tractor over the discussion with comments like, "I'm doing it through homework, it's about quality not quantity (he does the bare minimum), my grades are very good (not as good as he thinks) etc etc". Everything gets brushed off, diminished, he knows best. Always.

It's the oddest, most annoying thing. I've tried to talk to him about it but I don't get anywhere - except that he thinks we are telling him off, which suggests to me this is a defence mechanism. And we are really not telling him off in those moments, we're trying to open up conversation and be supportive about these school years.

I'm worried about his grades and how he's just going to not fulfil his potential. DH thinks let him get on with it and fail mocks etc, so he'll see for himself. But I don't know what to do.

OP posts:
Banannanana · 24/02/2026 18:05

I think this is pretty typical for his age, I know that doesn’t make it less irritating for you though!

Defence mechanism is spot on I’d say. Leave him to it for now, he’ll get a wake up call before the exams (mocks are usually it!). Just pick your battles and right now this isn’t one worth having. If he’s getting the grades he needs to make the next step in his life that’s enough for now. It’s him who has to live with it if he doesn’t get what he wants.

I’m not usually an advocate for hands off parenting and I do feel for you, I can imagine it’s irritating, but if he’s not doing too badly or behaving badly I’d just leave him to it for now and hope he gets a wake up call soon. He may be panicking more than he’s letting onto you anyway, that’s common with boys of his age.

Sensibletrousers · 24/02/2026 18:05

A question for you to consider: is he seeking victory, or accuracy? They can seem the same to the onlooker, but are very different drivers.

Does he want to “win” an argument, or prove someone wrong, for the sake of winning… or does he simply have a deep need for facts and absolute accuracy?

I can come across argumentative / opinionated / pedantic but I don’t care at all about winning or being the cleverest. I just really care about accuracy so if someone makes a bold statement based on dodgy misinformation, outdated or disproven science / data, or just on their feelings I feel the need to add actual facts to the mix! I realise it is annoying so censor myself and only speak up if it really matters….. I also LOVE IT if someone proves me wrong with better facts / accuracy and I gladly change my opinions whenever that happens! This is hopefully one of the skills your son will develop as he matures!

In the meantime my advice (I have two teen boys) would be this: let him. Let him FAFO in as many situations as you can whilst staying safe. Let him do things his way and either succeed (great! He was right!) or fail (great! He will learn!)…. And stop engaging in discussions he cannot be swayed on.

Pick your battles and change the subject.

TheIrritatingGentleman · 24/02/2026 17:52

ThePerfectWeekender · 24/02/2026 10:15

Astronomy or astrology? No wonder DS is mocking DH.

You don't think it's rude for a child to mock their parents?

sellersvin · 24/02/2026 17:52

LidlAmaretto · 24/02/2026 17:18

LOL brilliant and so true!

😁

MummyWillow1 · 24/02/2026 17:37

Spiritedlight · 24/02/2026 10:05

With respect, that doesn't really help me.

It isn’t meant to help you. It is meant to help him.

Stop talking at him and start listening.

Cherrysoup · 24/02/2026 17:24

‘I am not young enough to know everything’ as the play has it! None so cocksure as some teenagers.

poke955 · 24/02/2026 17:21

Reading this thread, and wondering if some men just don't grow out of it... 😅

LidlAmaretto · 24/02/2026 17:18

Firebox64 · 24/02/2026 17:13

Arguing with a teenager is like mud wrestling with a hog. You both get covered and the hog loves it.

LOL brilliant and so true!

smurfingbutgenerallynice · 24/02/2026 17:15

GasPanic · 24/02/2026 15:52

A dk encyclopedia of space ? lol. I would have chewed that up and spat it out at 15 years old. Probably at 10 years old.

He needs to go on the web. And it's cheaper.

Nasa site, Drbecky is a good youtube channel which is a bridge between "popular level" astronomy and more serious professional stuff, as is the Space site.

If you want to show him how much he doesn't know about astrophysics, a trip over to arXiv and download some of the astrophysics papers on there and have a quick read of some.

Chew up and spit out as in it is not advanced enough for you? But you aren't the one arguing without facts? It is definitely the right level for someone who doesn't yet know much about the subject and it is well written and interesting, it would give confidence to someone who wants to debate something as it gives a broad base of information.
It is written by those with expertise, even if not for people with expertise
Web is fine if you already have some baseline knowledge and you have a specific point to look up. And the nasa thing would be good for someone who already has an interest there.

Firebox64 · 24/02/2026 17:13

Arguing with a teenager is like mud wrestling with a hog. You both get covered and the hog loves it.

Galatine · 24/02/2026 17:08

This thread reminds me of the Mark Twain quote:
When I was a boy of 14, my father was so ignorant I could hardly stand to have the old man around. But when I got to be 21, I was astonished at how much the old man had learned in seven years.”

Sausages123456 · 24/02/2026 17:00

Havent read it all, but yeah I've got one of these at home. TBH I've backed right off, if he doesn't try hard enough now he's got a lot of work to make up next year in Year 11. My DS does bare minimum studying, did ok in his last set of exams but looks at me like I'm talking crap when I say you need to study more.
I remember being that age. They'll realise!

murphys · 24/02/2026 16:57

2026ontheway · 24/02/2026 13:13

Did you find the sport helped him (or you!) get through this stage? We’re just about to get into this stage!

I really think sport helped him in so many ways.
Socially - (he had always been socially akward) so being in a team was important
Physically - there is nothing better than a teen getting out there getting fit and in turn, letting off steam at the same time.

I can think of no negatives (ok maybe getting up at silly o'clock to travel for matches, cost of kit etc, but this is a given).

But for us I think the top benefit was having older male figures to look up to. I'm a single parent and he was the only male in the house. One of the sports is martial arts and he thrived so under the guidance of adult males that he could look up to. They really took him under their wing and he really flourished. They were also not afraid to put him in his place when necessary. MA is a very disciplined sport anyway, so being out of line wasn't taken lightly.

He did push his luck during those 14-16 aged years, like every boy in that age group that does. But he had a very good outlet for when he needed it too.

Honestly imo if any sport is an option for your ds, I really think it's so beneficial for them. My ds even travelled overseas with his, so that again was another really fantastic benefit.

RosesAndHellebores · 24/02/2026 16:27

@Alittlefrustrated and the previous poster who said this, it improves afyer 2/3 years, then they go to uni, and by 21 they are less argumentative and it gets better bit by bit. A hard Paddington stare at DS coupled with the words "do you actually want some help with your expenses for your Masters/PhD" worked wonders.

DD has never been argumentative but was challenging in different ways, like the eating, the anxiety, the cutting - give an argument any day. She's still at home, nearly 28, doing really well, great job.

UnctuousUnicorns · 24/02/2026 16:26

Alittlefrustrated · 24/02/2026 16:18

Bloody hell, I'vw got another 10 years if this?? 😭

Move to Scotland and pack them off to Uni at 17, preferably on a 5 year course, maybe PhD or other post grad after? It'll pass a few years away.

Slightly light-hearted, obviously.

Alittlefrustrated · 24/02/2026 16:18

RosesAndHellebores · 24/02/2026 10:24

@Spiritedlight this too shall pass. At 15 DS would argue the wall was black, not white. We tried hard to deflect the comments but it was a challenging time with little or no listening to other perspectives. He had uncontestable views based on many things: politics, the police, social justice, liberal arts v stem, his headmaster, whether the sun was fucking shining.

He's 31 now, married, expecting a baby and has a PhD. He started to revert to his chilled, sunny self when he was about 22, getting back to base at about 25 when I think the frontal cortex is fully formed. Be glad he has the confidence in his nurture and security at home to kick off at home. At this stage it's all about the export model.

Bloody hell, I'vw got another 10 years if this?? 😭

QuaintOrca · 24/02/2026 16:07

Teenagers are like this for a reason, psychologically there's huge changes happening in the brain where anything a parent says will be instantly wrong. It's part of teens developing independence skills and an ability to take responsibility. At the end of the day, if he gets shit grades it will teach him a lesson. Just because we know they are saying incorrect things doesn't mean we should always challenge them, being a teen/yo is all about figuring it out by yourself. As a parent, ask questions not criticisms. Teach him how to make his arguements stronger not louder.

We are a generation that's coddling teens way too much and it hinders their ability to become self assured adults. We learn best when we fail and we will be there to wipe tears and listen deeply but at 15, unsolicited advise will always be taken as a criticism.

GasPanic · 24/02/2026 15:52

smurfingbutgenerallynice · 24/02/2026 15:23

I have experience of this. I think teens talk like this when they are very stressed, they know they have left things to the last minute, they are anxious about the future, they know they haven 't done enough work, things like that. But they won't say that and in fact may not even have processed the thoughts fully enough to be able to give them words.

I suspect that your dc knows that they are clever but they also feel anxiety, perhaps about being behind.

In relation to the astronomy discussion, your dc is arguing and perhaps making things up because he wants to know about it and wants to have an intelligent discussion about it. So buy him a dk encycopeadia of space, it is brilliant and full of engaging fascinating info. And buy him other dk's while at it.

Your dc probably feels threatened by your dh for good reason on some level so worth thinking that through

Teens who coast (do well enough without trying at all - but not as well as they could) won't find their passions unless they really put their heart and soul into their learning. Coasting is not doing them any favours. I think it is worth talking about this and saying that you can support your dc's learning and that you can help him do well and say it a lot until it gets through

I wouldn't let your dc fail his mock to show him, it will affect his confidence and stress levels and make it even harder to revise.

While waitiing for him to listen, you could have a look at his work and make a plan for each subject about what you think needs doing to get him up to speed, and think of nice bribes to motivate each stage and then just force it through with him, getting him to learn bits with rewards at a time until his natural self motivation comes alive. I realise they are 15 but this is a hard time to be 15 and there will be a lot of influences in their lives taking them in the wrong direction.

It isn't a boy/girl thing incidentally. Girls are like this too if they know they could do well and secretly want to do better but feel a bit behind and stressed out.

Edited

A dk encyclopedia of space ? lol. I would have chewed that up and spat it out at 15 years old. Probably at 10 years old.

He needs to go on the web. And it's cheaper.

Nasa site, Drbecky is a good youtube channel which is a bridge between "popular level" astronomy and more serious professional stuff, as is the Space site.

If you want to show him how much he doesn't know about astrophysics, a trip over to arXiv and download some of the astrophysics papers on there and have a quick read of some.

UnctuousUnicorns · 24/02/2026 15:51

We heard you the first time! 🤣

ChimpanzeeThatMonkeyNews · 24/02/2026 15:46

I thought it was pretty obvious that the OP meant astronomy.

ChimpanzeeThatMonkeyNews · 24/02/2026 15:46

I thought it was pretty obvious that the OP meant astronomy.

ChimpanzeeThatMonkeyNews · 24/02/2026 15:46

I thought it was pretty obvious that the OP meant astronomy.

ChimpanzeeThatMonkeyNews · 24/02/2026 15:46

I thought it was pretty obvious that the OP meant astronomy.

ChimpanzeeThatMonkeyNews · 24/02/2026 15:46

I thought it was pretty obvious that the OP meant astronomy.

ChimpanzeeThatMonkeyNews · 24/02/2026 15:46

I thought it was pretty obvious that the OP meant astronomy.