Congrats to you, and congrats to your child for her learning to tell time on an analog clock/watch!
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the long hand should stand for the longer amount of time
Yes, I've heard other children express that logic over the years, seems intuitive, doesn't it? It often helps to know what kids are thinking. Here are some parental explanations to help kids remember which pointer is which:
- the short hand only needs to point in the general direction of an hour, a minute hand must reach all the way to the minute markers to be precise.
- the word "hour" is short like the hour hand, the word "minute" is longer like the minute hand.

This old post and this article vary a bit in sharing that learning to tell time on an analog clock is a developmental milestone for ages 5-8, and something a child can typically do after kindergarten.