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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Western Power Distribution say almost a thousand homes are without power due to damage caused by Storm Brian.
Helping young people 'earn, learn or serve' is among the policies Plaid Cymru will focus on ahead of the next election.
Trains have been cancelled and roads closed across Wales today after Storm Brian has been causing disruption.