In need of some advice...

My son attends an International school based in China. The school consists of mainly English/Australian teaching staff. The school is a member of Nord Anglia. My son's teacher, (year 3) continually makes errors in both spelling and punctuation. This has been of great concern for parents of the children in her class. Also the homework she produces is generally taken from the internet and has on many occassions contained mistakes. The photocopies we receive for homework are terrible! often unreadable.
We recently received spellings set by this teacher, for the children to learn and one of the words was spelt incorrectly and another had been duplicated! I'm concerned that she marks work incorrectly because a comma has not been used before the word 'and' (thought this was way out of date!) so what do you recommend?

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