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 warm and pleasant evening for many. Clear and cool overnight.
Continuing to be a fine and dry day across the country with lengthy sunny spells.
Leicester midfielder Andy King believes Wales can defy the odds at Euro 2016.