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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:
BlackeyedSusan · 24/02/2026 11:11

Spiritedlight · 24/02/2026 10:15

Yes, this is, without question, the worst stage of parenting so far. Completely unenjoyable.

What do you enjoy about him? Focus on that. It makes the rest a bit more bearable. They are still really cute when they are asleep! And not talking

Exam prep cost me a bloody fortune in rewards, but we had some really enjoyable meals out together and had chance to chat. A buffet restaurant have the opportunity for him to get up and get more stuff. Yours might like something different.

Blueartichoke · 24/02/2026 11:03

My Ds is 15 and can be like this, he won’t listen sometimes and thinks he knows best. We explain to him our reasoning behind what we are saying to him when he doesn’t listen but sometimes we just let him figure things out for himself, if he gets stuff wrong hopefully he learns from it. His mocks haven’t been great due to lack of effort and we have talked this through with him and when he feels like we are ‘getting at him’ we try and explain we just want to support him the best we can. I think that’s the key, support as this is a difficult period for them on the brink of GCSE’s and making decisions for the future.

Sharpcorners621 · 24/02/2026 11:03

Spiritedlight
About the defence mechanism thing; I think it is real and exists in the evolving teenage brain. I remember reading that experiments have proven that adolescents literally interpret tone of voice and expression as being more negative than they are in reality. It’s a preservation adaptation I think from way back when we lived in tribes designed to kick in when they leave the safety of the group? A bit like toddlers being fussy about foods once they can move and explore.

So although it’s infuriating, your timing and approach and tone need to be right.

Pick your battles, use humour, don’t be permanently on his case. Reserve proper talks for when you are on drives or engaged doing something else, Don’t confront him head on as it were! And make sure you spend positive moments with him too. Invent errands if you have to where you spend some time together and end it with a treat of some sort.

And of course the more avoidant, defensive and pretending to be on top of things they are, the more usual it is for them to be drifting, rebelling or having difficulties… so you are right to be concerned.

But you have to turn the responsibility over to him. Emphasise that he has choices. And that you believe in his competence and abilities. That you will offer back up support in whatever area he needs, he only has to ask, but it’s down to him now. And that you will be genuinely interested to know how he will use his time and all of these positive assets?

He has to learn self motivation at some point and the earlier the better.

Tell him that you love him so much that you want him to make the most of his considerable talents, so you will be checking in again about his academics over Easter or whenever.

Be serene and positive (even if you feel the opposite) because they need us to be steady when they are going through so much change. Don’t appear to be permanently anxious if you want them to share their worries with you. Get on with your own life and be a good role model.

Ignore the bluster such as contradicting your dh. That’s normal rejection of parental beliefs in order to establish his own identity and it’s healthy albeit a bit daft.

As for the know it all cockiness, we always took that as a sign that our dc needed more challenges and responsibility to test them.

One year we were so exasperated by our teen daughters’ negativity and superiority on holiday that we arranged through friends for them to help out with a youth volunteering programme where they were the only Brits and they had little money and few language skills and they had no choice but to make the best of it for a few days. They were much more pleasant to be around after that!

KaleidoscopeSmile · 24/02/2026 11:02

ThePerfectWeekender · 24/02/2026 10:15

Astronomy or astrology? No wonder DS is mocking DH.

Some other smartarse has already said this. Why not just assume that she meant astronomy?

BlackeyedSusan · 24/02/2026 11:02

It'll be really surprising how much you will both learn by the time he is 25!

This too shall pass.

In the meantime: nudge. Why do you think that? Do other sources have a different opinion? Etc.

Don't butt heads over it. It's really not worth it.

School work: Praise what he does do. gentle approach gets more results.

Send him links, text, talk in the car.

Good luck.

SatsumaDog · 24/02/2026 11:02

Yep, teenagers can be a bit like this. I just told mine that the ball was in their court. I was doing my bit, but if they chose to ignore my advice (re studying) then it was their choice. They are the ones who have to live with the results. For the rest of their lives. Universities generally only care about the grades on the piece of paper, for the first selection criteria. Obviously there are interviews etc for some, but you won’t get past the first gate if your grades aren’t good enough. Get that bit wrong through arrogance and inability to listen to parents and teachers then don’t come looking for sympathy from me. I’ll be able to do f all for you if you fuck up! Sometimes they need to hear it like it is.

MoreMaths · 24/02/2026 11:00

I often said to DH that I wished I was as clever or knew as much as a 15/16 year old. 😂

I think it's a very natural phase linked with growing up, hormones, identity and often friendship groups. They are beginning to establish themselves and navigate the world as a young adult whilst still needing the boundaries and security of being a child - and that can be hard for them to articulate in what we might see as a more mature fashion.

I read "Get Out of My Life, But First Could You Drive Me & Cheryl to the Mall?" by Anthony Wolf and would recommend it. Lots of helpful advice about picking your battles, trying to understand things from a teen perspective and dealing with common issues.

UnctuousUnicorns · 24/02/2026 10:56

Having had three teenaged DDs in my time (youngest is 16) I can assure you that it's not just a boy thing; girls can be just as big a know-it-all pain in the arse at times. It's part of adolescence but yes, it's a chore at the time. My older two are now 26 and 25, and both pleasant, hard working human beings, so hang on in there. It does get better.

Jimmyneutronsforehead · 24/02/2026 10:56

Is being a know it all not a rite of passage for most teenagers?

He will grow out of it, or he'll grow into it.

He'll certainly have life experiences that challenge his knowledge and he'll either be humbled or he will learn more and develop better critical thinking skills.

Channellingsophistication · 24/02/2026 10:55

I don't think I could tell my DS anything when he was 15 because he knew about everything, or it didn't work like that or that wasn't how life is these days...

I think this stage will pass, my DS is 18 now and he does actually listen and agree with what I say, sometimes anyway.

I think 15 is a difficult age with GCSE's approaching

allthingsinmoderation · 24/02/2026 10:55

Ahh the "know it all" phase.
I think its developmentally normal and the positive is the confidence and that can be helpful.
i think the advice to Listen to him,use facts rather than emotions to reason with him and let him find out through experience rather than being told are good ideas.
My daughter went through this phase and recently we discussed it when her son was exibiting similar ideas. My daughter said "you cant put an old head on young shoulders" i spat my tea out and asked of she remembered me saying that to her when she was 15 yrs old ....

Whattodo1610 · 24/02/2026 10:53

He sounds like a normal 15 year old 🤷‍♀️ I agree it’s difficult to live through, but he’s changing from a boy to a man, that’s just how it is. He’s finding his way, they all think they know it all at that age. You need to try to be the bigger adult and just rise above it. It really is just a normal part of growing up 🤷‍♀️

Nofeckingway · 24/02/2026 10:53

This

15 year-old know it all son
stickygotstuck · 24/02/2026 10:52

Likely a testosterone surge.
It gives males their arrogance and feelings of superiority. Totally unjustified and they tend to grow out of it if kept in check.

Just keep an eye make sure he does grow out. Contradicting him and pointing out when he's wrong should help.

PPs are right that by 17/18 it seems to pass all being well.

HRTQueen · 24/02/2026 10:52

I would often tell ds I had not idea how I got on in life without a teenage son

it was almost everything from driving to politics to how young women experience the world, there was nothing he wasn't an expert on and more knowledgeable about than I was

now he is a few years older the subjects of his expertise have lessened, his friends are very similar

He doesn't yet quite grasp male entitlement but he is aware of the concept of entitlement (more than I was at his age) and self awareness will come with maturity

Happyjoe · 24/02/2026 10:52

Friend of mines son was rude and know it all like this - but it lasted until he finished university. When he came home full time to live, he was know it all with his mum, rude, didn't listen..no matter what mum said or what she did, she was wrong and he knew better. But, although later than some, he grew out of it within a year. He's quite a nice lad now, balanced, no longer condescending and helpful to his mum. She stopped trying to correct him or take the bait, just walked away from him when he was rude and took away his audience.

I guess ride it out. If he really will not listen to advice or want to talk about his future education wise, let him find out the hard way. You can lead a horse to water etc!

UnctuousUnicorns · 24/02/2026 10:50

PinkyFlamingo · 24/02/2026 10:46

What on earth do you mean by that?!!

It's okay; I had to think about it for a few moments. My brain clearly hasn't engaged yet today. 😅

HelpMeUnpickThis · 24/02/2026 10:48

Spiritedlight · 24/02/2026 10:17

I don't know how that one sentence of yours could make me reflect, in any way.

That said, your comments here resonate. I do think my tone can be quite harsh sometimes and he points it out and I always apologise. We are very good at 'repair'.

That said, he gets tons of praise and nurturing and we are always talking

@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.

PinkyFlamingo · 24/02/2026 10:46

NoFiller · 24/02/2026 10:09

Your husband is very knowledgeable about astrology?

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

What on earth do you mean by that?!!

BauhausOfEliott · 24/02/2026 10:44

Honestly, I think your son sounds like a very normal teenager. I appreciate that it's massively annoying, but I don't think he's at all unusual to be going through an 'I know best' phase.

2026problemsandDDcanbeone · 24/02/2026 10:44

My DD was (and still is, to an extent) like this, if you don’t agree with her everything turns into a debate.

I used to think “whatever, life will teach her” but now I wish I had given her more of a pushback during her teenage years, it would probably have saved a few frustrations down the line.

Saying that, maybe your son is onto something regarding astrology and space………..

TheSandgroper · 24/02/2026 10:43

DH has been a 15 year old boy. You haven’t. They are different from us. If you have a good egg for a DH, take your lead from him.

I will say that with DD, I drank more gin that year as I prepared dinner.

thewonderfulmrswatson · 24/02/2026 10:41

I used to tell my children (all 4 are boys) "if you think you know everything you will learn nothing" my second son who will be 20 this year used to be like that.
It was always a case of using facts over feelings with him when he was been that way.
Feelings count for a lot amd were always taken on board but they don't overrule facts. Example "you can feel you're doing well science but fact is your grades say different"
He isn't like that now. I can't remember when it stopped but it did.

NorfolkandBad · 24/02/2026 10:40

DD was like that, but was doing well at school so not a big concern, she would make comments about things and then when asked to explain (as part of a conversation, not a confrontation) would effectively reply "it just is". We realised it was her peer group at school who were feeding her this nonsense and now she's a few years older, she's realised the same herself.

NamingNoNames · 24/02/2026 10:40

"When I was a boy of fourteen, my father was so ignorant I could hardly stand to have the old man around. But when I got to be twenty-one, I was astonished at how much the old man had learned in seven years."
Mark Twain

My father told me that one. My father wasn't ignorant but he was an arrogant smartarse.

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