Science lessons in most Welsh schools are good but assessment isn't robust enough, according to school inspectors.
Estyn also says sometimes, in primary schools, teachers pass on their science misunderstandings to pupils.
The Welsh Government welcomes the report which it says is broadly positive.
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A rather wet and windy evening, with rain in the north and showers elsewhere.
The 19-year-old's body was discovered in Builth Wells last month, just days after he was reported missing at the Royal Welsh Show.
The funeral has taken place of a one-year-old girl who died when a parked car rolled into a wall, which then collapsed on her.