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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:
GasPanic · 24/02/2026 13:26

I think he has to learn from his own mistakes. The problem is that at a young age that can be extremely costly. But to be fair you can retake exams if you fail.

Part of the problem at that age is that it is hard to understand what you don't know. The problem is that the publicly accessible stuff is normally at a very reduced level and it can be easy to fool yourself into thinking you believe you understand it, but the backing behind it is often very complex.

I remember getting to university the first time, and the thing that impressed me most was just how much knowledge there is out there. If you go into a library and look at the rows and rows and racks and racks of journals, it becomes quickly apparent that it is impossible to know everything, and even the stuff that you do want to know and specialise in is very complex and takes time to understand.

Re the more specific interests he has like astronomy, where does he get his information from ? Normally the web, but what sources ? If he for example goes on some of the more accessible sites for astronomy that's great, but may not be testing him in the way he needs to be tested. There are sites and channels out there that dig into issues in much greater detail and hopefully are capable of humbling him somewhat.

He doesn't sound like he is far away from being ready to go to Uni, at least at an academic level if not at a life experience level and when he gets there he will be able to focus all his skills on something a lot more challenging.

In the meantime, and in the few final years you have left together at home, maybe it is best to try to engineer situations where rather than your interaction with him being confrontational and a test of "who knows the most" on a subject try to orient them more towards shared experiences where you can listen together.

Teenagerantruns · 24/02/2026 13:23

Absolutely nightmare age. I would leave school work up to him. You cant force him.
If hes disrespectful at home just ignore there is really no winning an argument with a teenager. Just let the low level annoying things go.

Muffinmam · 24/02/2026 13:22

He doesn’t sound smart - he sounds narcissistic.

An intelligent person doesn’t argue about things they know nothing about.

My brother was/is incredibly intelligent. He was gifted as a child and coasted through school without any effort.

He argued about things he knew about and as an adult he is extremely well read and now works in a STEM field.

The problem with gifted children is they can burn out after highschool. They grow up knowing they were the smartest in their entire school and never had to try. At University they are often not the smartest and need to actually show up to lectures or they will fail.

There’s also the possibility that a person can be so intelligent they can feel ostracised from their peers and suffer terrible mental health.

I don’t think your son is at any risk of either of the above scenarios.

I suggest you encourage your son to pursue a trade if his grades are bad. Also, if he’s arguing about things he has no knowledge of he will completely fail at University as no one will put up with his BS.

As a parent it is your responsibility to prepare your children for society’s expectations and part of that is social intercourse. Without social skills he will fail to establish a social network at University or in any workplace which will very much limit his career options.

Jellycatspyjamas · 24/02/2026 13:22

At 15 he’s working things out for himself - his views, opinions, ethics and needs to be able to express these. As long as he’s not disrespectful I’d let him get on with it. I don’t need my kids to be right, have all the information or to agree with me - they’re learning, and trial and error is all part of that.

My DS can wax lyrical on something for ages, and I’m happy to listen even if I think he’s wrong, I disagree or whatever, the important thing is he wants to communicate with me. If it’s not dangerous or harmful, I’ll let him crack on.

meemeemammy · 24/02/2026 13:20

I do think this is an age thing, and I'm the centre of the universe type of thing. Their brains are still very much developing to see / hear others point of views. My 15 year old daughter is sometimes like this and comes out with all sorts! Doesn't listen, doesn't wear a coat when it's raining, promises me she's ready when she's not. I think it's just teenagers. Hopefully his grades will be ok

mumonthehill · 24/02/2026 13:17

Most used phrase here at that age was, we agree to disagree!! I think Ds thought I was very stupid and he was apparently always right. It does change, infact it is surprising how suddenly you are asked for advice and support. I was all knowing when it came to uni applications, buying a house, interview hints. You just have to laugh it off really.

meemeemammy · 24/02/2026 13:16

NoFiller · 24/02/2026 10:09

Your husband is very knowledgeable about astrology?

Not surprised your son is telling him he’s speaking bollocks.

I'm sorry, but this just made me laugh out loud ( sat in Tesco cafe on my own- thinking of the Dad reading the horoscopes) I'm really sorry.

BunnyLake · 24/02/2026 13:16

It’s a phase. I went through it and my kids did. We think we know everything at that age and people with decades more life experience know nothing.

2026ontheway · 24/02/2026 13:13

murphys · 24/02/2026 10:24

I am not sure there are many that can say they got through parenting a 15 year old boy completely unscathed.

Some will come along and say their 15 year old's were perfect specimens of the human race and they never ever pushed their luck or boundaries. To this I say that they just forgot what is was really like that year.

My ds is very sporty and was in various teams at that age. So the parents from each sport would socialise after events quite often. So there was a big ratio of 15 year old parents in one place at one time. We were definitely not alone in our thinking, and most of the boys played up in one way or another that year.

But they have mostly all turned out fine young men OP. It is just important to lay the ground rules of what is acceptable and what is not.

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

Spiritedlight · 24/02/2026 13:12

To clarify again (I have already clarified this) - I meant astronomy.

OP posts:
Julimia · 24/02/2026 13:12

You clearly have a .very normal 15 year old.Jut let him get on with it . If he asks for help thats fine but otherwise back 9ff. ¹ He will learn, so be it if its the hard way.

Friendlygingercat · 24/02/2026 13:12

Unfortunately kids who are very bright are often a bit lazy with it. Instead of planning and working towards a goal they tend to wing it and /or leave everything until the last minute. As a result they dont achieve their potential. I taught some really bright young people at uni and they rarely got a 1st. The ones who did were not perhaps quite so bright (but smarter than average) and smart enough to know that preparation and self discipline are preferable to winging it.

Mrandy · 24/02/2026 13:11

It’s because you mean astronomy (I think!)

Spiritedlight · 24/02/2026 13:09

Thanks to everyone, some great thoughts here. I've only had time to skim but I'll be writing notes later.

Good to know that others are going through it

I do need to meet him with support, praise and love and let him work it out.

I need to work very hard at losing the harshness. That's what I can control. It's just my tone, never the words. But that it itself can be a barrier. I do know this.

OP posts:
Spiritedlight · 24/02/2026 13:08

DysmalRadius · 24/02/2026 11:37

Op, this is honestly not intended to be a 'gotcha' but in this thread you made a mistake in your OP, and when a poster pointed it out, your initial response was chippy and dismissive without actually reading what they wrote or checking what you had written.

Does that sound like your son at all?

I am only pointing this out because the number 1 thing that annoys me in my kids is when they demonstrate the behaviour traits I like least about myself.

You're quite right

OP posts:
Spiritedlight · 24/02/2026 13:04

HelpMeUnpickThis · 24/02/2026 10:48

@Spiritedlight

I too would find the arrogant back chat very trying.

I agree with PP that rather than make it a debate I would just detach - grey rock, change subject etc. I wouldn’t get entangled in debates that wind me up or where I know there is a big, demonstrable difference in knowledge/experience and the other party is not open to listening or learning. I just don't have the patience for it. Same applies for adults too BTW.

I would really struggle with the lack of academic “focus”. I have put that in quotations because he might be focused but not appreciate being micro managed. Or not able to see cause and effect due to lack of experience and immaturity. For this I’d suggest you pick your hard line conversations and be less vocal about the rest. Sometimes people only learn through consequences.

Just reading your posts I do think you sound quite negative. You have repeatedly said “this is the worst stage of parenting”. Gently, your DS does not owe you a specific parenting journey. He is trying to figure himself out and let’s be honest, he doesn't really know how to do this. Your job is to support not be an oppressive critic. Try to reframe your thoughts (and perhaps words?) about how you are finding this stage of parenting. It’s quite clear you are not enjoying it. Maybe he is picking up on this low key disdain?

What I DO think you urgently need to work on is your critical or “harsh” tone, as mentioned by you. This is absolutely horrific to live with. Ask me how I know.

It’s ok to be ambitious for your son but living with someone who is constantly nit picking, correcting, giving unsolicited advice, telling you are wrong is a recipe to a distanced relationship as soon as independence is gained and years of therapy to unpick the resentment. Speaking from
lived experience.

Good luck.

Thank you for the advice and the feedback. It's sobering re: harsh tone - that said, I am VERY aware of it, he knows I'm aware of it, and it's countered by a ton of praise, love and unabashed pride in who he is. But my own traumas and upbringing certainly contributed to my directness and sharpness - it's no excuse, but it's something I am very aware of and constantly try to work on.

Thank you for the important reminder - my relationship with kids is of the utmost importance.

OP posts:
BoredZelda · 24/02/2026 13:03

VenusClapTrap · 24/02/2026 12:46

Currently walking on eggshells around my 15yo know-it-all and highly combustible dd, so I sympathise. It takes some navigating. Sometimes Dh says to her ‘Now try saying the same thing, in a friendlier way’ and that does seem to give her pause.

Urgh. Girls don’t have to be nice.

BoredZelda · 24/02/2026 13:01

15 year olds are supposed to know everything. It’s their job. Your DH is right, natural consequences are the best way.

My teenager is exactly the same, will argue black is white and has the self confidence to express her opinion. I love it, it’s what I raised her to do. Sure there are rough edges but they will be knocked off in time.

I also hate when people say their kids won’t fulfil “their” potential. What you mean is, you think he won’t live up to your expectations.

Freya1542 · 24/02/2026 12:59

Spiritedlight · 24/02/2026 10:22

I mean astronomy!! I'm so sorry to the poster who I said was rude. I'm running into a meeting but will respond more when out

@PashaMinaMio

@Spiritedlight addressed this at 10.22 😊

Snap! @CustardySergeant

CustardySergeant · 24/02/2026 12:57

pinkyredrose · 24/02/2026 12:44

Did you mean Astronomy Op?

Yes, she said so in her post at 10.22.

NotSmallButFunSize · 24/02/2026 12:51

murphys · 24/02/2026 10:24

I am not sure there are many that can say they got through parenting a 15 year old boy completely unscathed.

Some will come along and say their 15 year old's were perfect specimens of the human race and they never ever pushed their luck or boundaries. To this I say that they just forgot what is was really like that year.

My ds is very sporty and was in various teams at that age. So the parents from each sport would socialise after events quite often. So there was a big ratio of 15 year old parents in one place at one time. We were definitely not alone in our thinking, and most of the boys played up in one way or another that year.

But they have mostly all turned out fine young men OP. It is just important to lay the ground rules of what is acceptable and what is not.

Well, mine was only this age last year so definitely can remember it and it honestly wasn't that bad..... 😉 Him being 3 was far worse!

That said, he is a typical teenage boy, I guess some of it is just what you are prepared to ignore. I am told he is hard working and polite outside the house so I am happy to let a lot of the grunting and eye rolling at home slide.

PashaMinaMio · 24/02/2026 12:50

NoFiller · 24/02/2026 10:09

Your husband is very knowledgeable about astrology?

Not surprised your son is telling him he’s speaking bollocks.

Dear OP,
I think you meant Astronomy? The study of stars and beyond.

Astrology is quite different; the study of birth dates and signs! Check your original post. Predictive text has got the better of you!

VenusClapTrap · 24/02/2026 12:46

Currently walking on eggshells around my 15yo know-it-all and highly combustible dd, so I sympathise. It takes some navigating. Sometimes Dh says to her ‘Now try saying the same thing, in a friendlier way’ and that does seem to give her pause.

pinkyredrose · 24/02/2026 12:44

Spiritedlight · 24/02/2026 10:14

What kind of comment is this? That's just rude

Did you mean Astronomy Op?

SpinandSing · 24/02/2026 12:36

Astrology/Astronomy misunderstanding has given me a good giggle.

I have two dds who are a little bit like this OP - one more than the other. To be honest, she's 25 now and she stills leaps to self-defence with gentle conversations ... she can't bear for me to question anything really and never has been able to. I just totally let it go now as I can't be bothered with the conflict. I was reflecting back on her teenage years the other day and do I wish I'd challenged her a bit more? Yes, I think I do, but I'm not sure it would change the outcome. I think her personality leans towards defensive and stubborn, even though she can be lovely and sweet, and with questioning her all it will lead to is arguments and, probably, the same outcome anyway. Some people are just wired differently. We do have lots of calm conversations and she takes in a bit of experience and wisdom from me now ... but she has to be the one to invite it. It's really hard - I get it. And I am very careful with my communication style with her - I manage a lot of people and am used to different personalities ... in fact, I'm quite good at it. But kids at home ... much harder as they don't really respect your authority ... not truly. This is why they need to grow up and fly the nest! He'll resent you and just avoid telling you anything if you aren't careful.

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