Dd is 3.5 we have been using 'the step' quite successfully for over a year. In the first instance it was mostly as dd would get herself really over excited and then not listen to anything asked of her - the step worked really well to calm her down. We also use a lot of praise for good behaviour and toy confiscation.
Recently the step has becone really ineffective, actually making dd's behaviour terrible but I'm not sure what to do - This morning dd1 hit dd2 (18m) as she had a toy she wanted so I asked her to go to the step up until recently she would have reluctantly but eventually gone to the step we woukd have talked etc and then over and done with. Today dd got very angry screaming and shouting because she didn't want to go - behaviour when I asked her to sit on the step was much worse than before hand. We need an alternative but don't know what.
But surely the point of the naughty step is about teaching impulse control?
I have a 3.5 year old dd1 too. I'm not a big user of time out, but for things like hitting her sister I don't see a more appropriate penalty. I don't expect her to be delighted to be put in time out, but the point is rather for her to learn it is more pleasant to manage her desire for a toy than to hit her sister and go to time out?
I do feel for you. My dd1 has always been quite easy going, but in the last few months her emotions just seem so strong, when she wants something it's really hard for her not to grab, push, hit. Most of the time we can talk about it (I find naming her feelings seems to help her) but if she hurts someone I think time out works quite well.
I think that's just normal 3 year old behaviour struggles. I'd carry on with it if it works eventually even if you have a battle in between. Perhaps supplement with non-punitive stuff too, talking about feelings, alternatives, having a special big pillow she's allowed to hit when she feels like hitting something, etc.
We get dd to go to her room 'to calm down'. She understands why and I don't think she sees it as a punishment. She is a little older (5) but we have been using it for a couple of years. She will usually come down after a few minutes and want a cuddle and we tend to get a 'sorry' whispered in our ear. Sometimes we go up to her and she'll be playing or reading a book.
We never liked the naughty step idea, as we felt they were still right there in the midst of the problem, when what you really want is to stop the behaviour without escalating it.
Our method also helps the adults to keep calm as it gives everyone a couple of minutes breathing space (good in your example in the OP of hitting).
If my 4 year old refuses to sit on the step, defiant, answers back etc then he gets carried to his room and has to sit in there instead. If he refuses to sit nicely in there then the length of time he has to stay in there goes up. Not sure if that's an 'approved' strategy but that's what we do anyway.