What to look for if you suspect your child's teacher isn't very good

[Sparklywheeelbarrow]

Have NC'd for this.

If your child is a bright and capable child but you suspect their teacher is letting them coast rather than challenging them or getting them to reach their potential?

The reason I ask is that my dd is in a class with a teacher who may be doing this. The teacher in question used to work with the parent of another child in the class (job share) and long before this teacher joined our school the parent (whose judgement I totally trust) had mentioned how disorganised she was, that she was very wishy washy when it came to keeping up with the curriculum and didn't stick to lesson plans etc - then she joined our school and is now teaching our kids ... so much uneasiness ensued.

We are now halfway through the year and my dd has complained many times that this teacher treats them 'like babies' (they are year 4 for context), which makes me wonder if she is underestimating the capabilities of the class and has lower expectations of them than she should? I believe she taught Year R prior to this, if it's relevant.

So I'm wondering what I ought to be looking out for here - other than the fact that my dd doesn't like her, and that other parents aren't happy with her. What should good a teacher of Year 4 be doing to get the best out of a class?

I've no memory for names either. I always assume everyone is better than me at it. Yes, it does speak to a good memory (or a much repeated story!).

To my understanding it was neither discussing a colleague from a former workplace, after that person stopped being a colleague but before they started being OP's DC teacher; nor discussing a current teacher who happens to be a former colleague.
I'll offer up a third, in-between interpretation: OP's friend discussed her then current job-share colleague with her friend. That's more problematic IMO than discussing a former colleague after you, or they, have left that job.
Then, somewhat later, that former colleague turns up at OP's and friend's DC school, friend goes 'Oh that's that colleague I used to tell you about!'

On the scale of wrongness of discussing a job-share colleague, discussing a former colleague with someone who who doesn't know them and currently has nothing to do with them is probably the least bad. Don't know what's worse though, discussing a current colleague with someone who doesn't know them, or discussing a former colleague with someone who now does know them/has something to do with them. I tend to the latter I think.