Our son, 3.75 years old, gets frustrated fairly easily (e.g. zipper gets stuck when he dresses, tower of building blocks collapses unintentionally). Often this results in him stomping and/or throwing the item(s) that caused the frustration and/or screaming at the top of his lungs.
We do not want to allow such behavior. Currently we keep it at bay with severe punishment: After such a scene we immediately shout at him "One more stomp/throw/scream and you get 3 hits on your butt!" - and follow through with that if he goes on. As a result, such outbursts end quickly. Before we implemented this punishment, he had much longer outbursts, so it does work. But I feel that this is a rather unhealthy way of solving the issue: We make him suppress his frustration and anger, and I think suppressing is no healthy long term solution.
If we parents get angry, we swear (and find that acceptable). So after such a scene and after he calms down, we tell him he can swear instead of stomping/throwing/screaming, like "Stupid zipper, why do you always get stuck?". And that if toy X frustrates him, he can just play with something else and so "X got what it deseved". But I have not observed any change in behaviour so far (we do it that way for a month or so). I assume he is unable to implement it because the feeling of anger is just too strong to allow his conciousness to correct his impulse.
Any ideas on how to handle the issue differently?
I would like to add that the issue I consider unhealthy is NOT that we spank him. I know this is controversial. We use spanking not out of anger or lack of impulse control on our side; we use it as a disciplinary method. Because all other methods we tried do not work (e.g. timeouts). So if you are uncomfortable with this, imagine I had written "you get a 10 minute timeout" instead of "you get 3 hits on your butt".
The issue I consider unhealthy is the fact that we teach him to suppress his anger without any way of letting it out or redirecting it. Because we don't know how. This is what I need ideas for.