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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:
Spiritedlight · 28/02/2026 19:20

Sharpcorners621 · 27/02/2026 14:37

It depends what you mean by “leaving them to it” though doesn’t it?

For example, down thread, I advised turning responsibility for their study over to them, but when I say that, I didn’t mean abandoning all expectations of them, or not checking up on their progress, or not being interesting in their study, exams, outcomes and future career choices.

Imho, if a lad hasn’t got in to the hang of self study and motivation around about the age of fourteen, any amount of nagging is going to be counter productive.

He needs to learn to discipline himself first and foremost; there’s only so much you as a parent can do for them. But of course, stay engaged, stay interested, be there, and keep the lines of communication open. And stand in the side lines and facilitate a good study environment, be a good role model and respond to requests and questions. But the actual study and how much they do, is down to them.

I think that’s what most people mean anyway.

I don't agree with this line "Imho, if a lad hasn’t got in to the hang of self study and motivation around about the age of fourteen, any amount of nagging is going to be counter productive."

A 14 year old boy is wildly different to a 15 and 16 year old boy. I've noticed a huge difference in a year. I don't think that you can write off them finding motivation and drive if they haven't found it by 14.

OP posts:
focused1 · 27/02/2026 19:46

Gingganggoo · 27/02/2026 12:16

He's being cocky because he is 15 - also, fear of admitting he isn't all knowing probably makes him jump to a defensive position. It is annoying but he will learn the hard way.
Also, he isn't too old to lose privileges like access to the internet or his phone. Perhaps he needs a wake up call about who controls things at home, and it shouldn't be him!

Cocky can sometimes be the only way teens express but also mask their fears. Not many admit that they are finding school and the work tough . Apart from hormones , females , being seen as being tough and strong I feel with most it is trying to give that don’t give a damn attitude to all as a coping strategy.

Sharpcorners621 · 27/02/2026 14:37

smurfingbutgenerallynice · 27/02/2026 13:03

I just clicked on one of the related threads listed at the bottom of the page, and one is a question about whether to teach/enforce good study habits/give support with teens of this sort of age or whether to leave them to it, and there was voting, and 68 percent recommended leave them to it.

I thought it was really interesting, and I think strongly that the majority is completely wrong in this case (but obviously that is just my opinion).

It depends what you mean by “leaving them to it” though doesn’t it?

For example, down thread, I advised turning responsibility for their study over to them, but when I say that, I didn’t mean abandoning all expectations of them, or not checking up on their progress, or not being interesting in their study, exams, outcomes and future career choices.

Imho, if a lad hasn’t got in to the hang of self study and motivation around about the age of fourteen, any amount of nagging is going to be counter productive.

He needs to learn to discipline himself first and foremost; there’s only so much you as a parent can do for them. But of course, stay engaged, stay interested, be there, and keep the lines of communication open. And stand in the side lines and facilitate a good study environment, be a good role model and respond to requests and questions. But the actual study and how much they do, is down to them.

I think that’s what most people mean anyway.

smurfingbutgenerallynice · 27/02/2026 13:03

I just clicked on one of the related threads listed at the bottom of the page, and one is a question about whether to teach/enforce good study habits/give support with teens of this sort of age or whether to leave them to it, and there was voting, and 68 percent recommended leave them to it.

I thought it was really interesting, and I think strongly that the majority is completely wrong in this case (but obviously that is just my opinion).

smurfingbutgenerallynice · 27/02/2026 12:46

Gingganggoo · 27/02/2026 12:16

He's being cocky because he is 15 - also, fear of admitting he isn't all knowing probably makes him jump to a defensive position. It is annoying but he will learn the hard way.
Also, he isn't too old to lose privileges like access to the internet or his phone. Perhaps he needs a wake up call about who controls things at home, and it shouldn't be him!

I don't think teens should be allowed to be rude or disrespectful, and that sort of behaviour should be verbally picked up
But I am not sure that threats about privileges would be proportional for a teen telling you "quality not quantity" and that you are wrong about astronomy?!

Gingganggoo · 27/02/2026 12:16

He's being cocky because he is 15 - also, fear of admitting he isn't all knowing probably makes him jump to a defensive position. It is annoying but he will learn the hard way.
Also, he isn't too old to lose privileges like access to the internet or his phone. Perhaps he needs a wake up call about who controls things at home, and it shouldn't be him!

smurfingbutgenerallynice · 27/02/2026 11:51

JustMeAndTheFish · 26/02/2026 12:38

With all due respect this isn’t always true and depends on the career/job he actually wants.
In general I agree that every step on the education ladder is just that - a way of progressing to the next step.
My daughter works in STEM, has two post grad degrees and has recently been asked about her GCSE and A level choices and results.
The post she was applying for had over 150 applicants so I presume they were all equally qualified and they had to differentiate somehow.

GCSE results are looked at when applying for jobs in law too.

smurfingbutgenerallynice · 27/02/2026 11:41

focused1 · 26/02/2026 16:57

As a mum of 5 boys which are 10 years apart I know most 15 year olds put on the 'I am not worried ' front . Check with subject teachers at school how he doing then have more of a practical talk of what he plans to do post school . Both attend a careers advice session and see they will explain grades he needs for apprenticeships , college , uni to give him some goals .
Distraction next year might be a part time job so he understands having his own money and an excuse to part him from some of his friends who might be thinking the same things but deep down they are also worried and think there is no other pathways apart from intense study .
After exams I would ask for school support . Group study as asking any 15 year old to study on their own even for 30 mins is totally stupid ,
Wouldn't threaten anything but get others outside the family to provide help.He isn't laughing inside - this is usually a front at this age.

Good post.

smurfingbutgenerallynice · 27/02/2026 11:39

Spiritedlight · 25/02/2026 19:53

I don't know. But it feels weird letting him fail to teach him a lesson. It goes against my maternal instinct.

It is not a good idea to let him fail.
Work out what he needs to do by looking at his books, and tell him what he needs to do, and tell him that whatever he says you are there to support him.

And give him resources which correct his wrong ideas in relation to astronomy and everything else. The DK encycs are amazing even for this age (younger kids read them) because of content but also because they open up discussions. Your dc could be talking to your dh at the same level in relaton to astronomy and that is more what you want. The DK Space encyc for example would tell your dc a lot of information and give him confidence to discuss and to explore the area himself. As for politics or other subjects, there is no right or wrong, give him your informed opinion and say "but this is just my opinion, I am not necessarily right" and only correct factual errors. It will end up with your dc asking your opinion on stuff, knowing that you won't force him to agree

So for exams: give structured help and rewards
Other stuff: give resources and give your opinions but keep it at debate level rather than telling him

The posts telling you to let your dc fail are bonkers. If your dc is not doing as well as they should whether they tell you the opposite or not. No 15 year old, ever, said "oh dear I panned in my mocks, I had better work hard now".

cantbebothered101 · 27/02/2026 08:44

Op here’s a good link on brain development it might help a bit!

www.instagram.com/p/DVBxAZykiIh/?igsh=bWYwbmhzZ3ZvYWM%3D&wa_status_inline=true

Foggyflumpet · 26/02/2026 20:21

Been thinking about this a bit more. I wonder if it's because you FEEL everything so much more as a teen. I do have (suppressed!) Memories of KNOWING I was right and NEEDING other people to recognise it.

I no longer care😄 There really do become bigger things to think about. And you realise that it's no way to keep friends😄

focused1 · 26/02/2026 16:57

As a mum of 5 boys which are 10 years apart I know most 15 year olds put on the 'I am not worried ' front . Check with subject teachers at school how he doing then have more of a practical talk of what he plans to do post school . Both attend a careers advice session and see they will explain grades he needs for apprenticeships , college , uni to give him some goals .
Distraction next year might be a part time job so he understands having his own money and an excuse to part him from some of his friends who might be thinking the same things but deep down they are also worried and think there is no other pathways apart from intense study .
After exams I would ask for school support . Group study as asking any 15 year old to study on their own even for 30 mins is totally stupid ,
Wouldn't threaten anything but get others outside the family to provide help.He isn't laughing inside - this is usually a front at this age.

Lunaticmess · 26/02/2026 16:26

JustMeAndTheFish · 26/02/2026 12:38

With all due respect this isn’t always true and depends on the career/job he actually wants.
In general I agree that every step on the education ladder is just that - a way of progressing to the next step.
My daughter works in STEM, has two post grad degrees and has recently been asked about her GCSE and A level choices and results.
The post she was applying for had over 150 applicants so I presume they were all equally qualified and they had to differentiate somehow.

True. A lot of employers ask about A-level results these days because they are still considered harder than degrees for a lot of professions.

Soberinthecity · 26/02/2026 13:22

BlueMoonBlueCheese · 24/02/2026 10:15

Maybe it was intended to make you reflect.

Why does he think you are telling him off?

Children's communication skills are a reflection of their parents communication skills or lack thereof.
Maybe you don't realise it but the tone you are using is critical, negative etc.
Maybe you never praise him, it's hard for any reader to say with the limited information.
Maybe try and take him for a meal or a walk and talk about the good things in his life and gently try and find out if there is anything worrying him?

definitely all of this. A walk or drive and talk is far better as there is no eye contact and therefore nowhere near as confrontational. Maybe he doesn't like school at all...I was the same at 15; couldn't wait to get out of school and I always knew best. Bright but F*cking lazy and complacent. I'm 54 and a psychotherapist and ex-teacher (go figure...) so it didn't do me any harm.

point is - there may be other things going on; as if being 15 isn't hard enough! It's too old to be childish, too young to be an adult....they're all over the place. Are there other siblings? there's so little info provided it's hard to know what advice to give but patience, clear & consistent boundaries and a ton of love will be a good start. There are way more important things in life than good grades.

JustMeAndTheFish · 26/02/2026 12:38

HelenaWaiting · 24/02/2026 10:11

We dealt with something similar by dealing solely in facts - what does he want to do next, what grades in what subjects does he need, where is his progress towards those grades. That's all GCSE results are, at the end of the day, just a passport to the next phase. 8s and 9s are nice, but within a very few years, no one will care or even ask what GCSE grades he got. Take the emotion out of it, stick to the facts. Worked for us.

With all due respect this isn’t always true and depends on the career/job he actually wants.
In general I agree that every step on the education ladder is just that - a way of progressing to the next step.
My daughter works in STEM, has two post grad degrees and has recently been asked about her GCSE and A level choices and results.
The post she was applying for had over 150 applicants so I presume they were all equally qualified and they had to differentiate somehow.

Evidemment · 26/02/2026 12:11

For what it's worth OP there's evidence in this thread that some folks do retain the trait of self importance and continue assuming they know better even into adulthood. Goes to show you're not alone in suffering this!

(See the endless posts about astronomy/astrology and repetitive Mark Twain quote - the thread/relevant info clearly isn't read before jumping to give their enlightened input 😉)

creeeepy · 26/02/2026 12:08

15 year olds - boys and girls - can be the MOST irritating, rude and, obnoxious beings. I know I was too.
Thank goodness 99% of them grow out of it into lovely humans.
You’ll laugh about this in years to come.
Stay strong and stick to your principles.

Popsielady · 26/02/2026 09:57

Yes we’re getting exactly the same with our son, in his final year of a-levels any advice gratefully received!

LaDamaDeElche · 26/02/2026 07:45

Although annoying it’s pretty standard teen behaviour. My 16 year old DD is very similar. I try not to get into it with her. She’s very into chat gpt, so when she’s talking rubbish with full conviction I tell her to ask chat and that usually ends the know it all conversation 😂

Regarding school it’s a tough one as obviously you want him to do well. You can’t force someone to study though. Is there any kind of intermediary, like a teacher he respects or older teen, who could have a conversation with him? I think with strong-willed teens like this often punishments don’t work, but perhaps something to motivate him instead? Something he wants that you’ll get for him if he gets x grades in his mocks, maybe.

Poodlemother4 · 26/02/2026 07:34

This is quite natural in teenagers. They think they know everything and only experience will teach them that they don't. That is why young people join the army to fight, thinking that they are invincible and nothing bad will ever happen to them. I agree, it is tedious, also pointless to argue. I would suggest that future conversations could be conducted like this: You ask a question about how he would cope with a certain situation eg the unlikely event of your house being struck by an earthquake. What would be the first thing he would do? Where would you all live? What about water and food? Heating lighting and clothing, bearing in mind that all has been consumed by fire. Don't argue with him, just listen to what he has to say eg "I see, and supposing you couldn't immediately find food, what would you do?" If the answer is go to a friend's house, you can say "Ah, but their house has fallen down as well. And so on and so on. Do it in small sessions, so you don't make his brain implode, it will teach him that he doesn't have all the answers and that maybe parents might have some which fit. Hope this helps.

persephonia · 26/02/2026 02:59

persephonia · 26/02/2026 02:53

Do you mean astronomy or astrology?

Sorry I just saw you already responded to someone else re the astrology thing.

As others said it's a phase. A very annoying phase. I was a know it all at 15/16. And TBF I do think I was right about some things but it still must have been super annoying for my mother. Possibly he will discover politics next which will be really fun for all of you. But I think it's part of learning more about the world, especially moving beyond the scope of your parents and getting more independance and independent thought. Which is all lovely. It tends to result in some annoying know it all behaviour short term.

persephonia · 26/02/2026 02:53

Spiritedlight · 24/02/2026 10:14

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

Do you mean astronomy or astrology?

Chickadee001 · 26/02/2026 02:47

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.

I'm guessing you mean ASTRONOMY?!

ForQuirkyFawn · 26/02/2026 01:23

Typical 15 year old then....

TheCheekyCyanHelper · 25/02/2026 23:55

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.

This is completely normal for teenagers. They grow out if it, or become politicians.

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