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 dry night with clear skies across much of Wales. Temperatures will fall widely below zero, so if you're out and about, wrap up!
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Dutch-owned Abellio Rail Cymru (ARC) has ended its tender for for the next Wales and Borders rail franchise.