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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:
frozendaisy · 24/02/2026 10:13

Yep let him fail his mocks he will have to turn it around if he wants to

at least then you will have lower marks in black and white to suggest perhaps more effort and the teacher’s advice could be listened to

murphys · 24/02/2026 10:12

15 year old boys and generally a bit of a nightmare OP.

The year that my ds was 15, the parents of the whole year were called in to the school at the start of the year. We were told that this could quite possibly be one of the hardest years of parenting due to their age. Hormones, changing bodies, the odd age of not a child and not an adult, so they don't quite know where they fit.

You and dh need to be a team and set good boundries. And then grit your teeth a lot and in a year or so, he will become pretty nice and normal again.

HelenaWaiting · 24/02/2026 10:11

Spiritedlight · 24/02/2026 10:05

With respect, that doesn't really help me.

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.

Toddlerteaplease · 24/02/2026 10:11

PointlessTrip · 24/02/2026 10:07

Has he always been like this? I have known some boys go through phases of this cockiness. It does seem to pass with maturity. Very tedious to be around though!

A friends son is exactly the same. His parents just laughed it off and said he was going to be a politician, but I found annoying and rude.

NoFiller · 24/02/2026 10:09

Your husband is very knowledgeable about astrology?

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

PointlessTrip · 24/02/2026 10:07

Has he always been like this? I have known some boys go through phases of this cockiness. It does seem to pass with maturity. Very tedious to be around though!

Spiritedlight · 24/02/2026 10:05

BlueMoonBlueCheese · 24/02/2026 10:03

Sounds like he needs a jolly good listening to.

With respect, that doesn't really help me.

OP posts:
BlueMoonBlueCheese · 24/02/2026 10:03

Sounds like he needs a jolly good listening to.