DS so negative about everything

[millimat]

He's 13 and very lucky as he is very bright and also athletic. Most things come very easily to him.
However when anything is a bit of a challenge he goes very negative then throws a complete strop. This could be from asking him to find some new clothes to suggesting he gets his homework done to being on a family day out where he firebrand hey his own way.
How can I get him to become more positive and take challenging things to not be bad?

I mean this nicely but are you a positive person ? Positivity is learnt behaviour

I get very anxious and do see things as half empty a lot, but try not to let it show. DH is not like that. The situations where ds loses it are not when I would be negative though. He just went give things a try and shuts down so suggestions fall on deaf ears.

We do praise him for effort and have never pushed for him to be top or anything.

This is a tough one. I have one like this and I'm trying to get them to practice gratitude. I can't tell you whether it works as am inconsistent! But am going to give it another go. I also try to make her realise it's ok to fail as long as you get back up again. I suspect it is partly a self esteem issue too.