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Best Polish Primary school in Wroclaw for Foreigners [17]
There are very few, if any, members here with children, living in Wroclaw. But here is a link to a ranking of public and private primary schools in the city with reviews from some parents and past pupils. Use Google's 'translate this page' facility to read it if your Polish is limited.
waszaedukacja.pl/ranking/wroclaw/szkoly-podstawowe
I was a primary school teacher in Ireland and though it's very different there, some of the same basic principles apply as far as your child is concerned.
1) Don't worry about the language. The child has basic language skills already and daily exposure, especially among other children (they really do learn from each other) will be a big help. Don't worry about academic progress for the time being.
2) The smaller the school, the less daunting it is for the child. Apart from being less overwhelming, the class sizes are smaller and the child has a chance of a bit more time and attention from the teacher. You don't say how old the child is, but if they're new to school, then the smaller the better is definitely the case.
3) If you can get a school near to where you live that meets those requirements it's preferable, as friendships formed in school are easier to develop and maintain if children live near each other.