Children should learn what their country achieved and what it did wrong. I don't see why those aims should be treated as opposites. A national history that leaves out slavery and imperial violence is dishonest. One that offers little except reasons for shame is incomplete too.
The purpose should be to help young people understand the country they have inherited, including why there are things worth preserving and things that needed changing.
Pride needn't require ignorance
There was good reason to challenge versions of history that treated empire mainly as an adventure and gave little attention to the people subjected to it. Leaving those experiences out makes it harder to understand both the past and its consequences.
But correcting an omission isn't a reason to make another one. Constitutional developments, scientific work, social reform and struggles for liberty are part of the history as well. So are the people who opposed abuses while they were happening.
A country isn't a single actor with one intention across the centuries. People fought over what it should do. Teaching that conflict is more useful than asking children to decide whether Britain was fundamentally good or fundamentally bad.
An inheritance people can understand
I worry about an account that makes belonging seem embarrassing. We ask people to care for a country, accept obligations to strangers and improve institutions they didn't create. It is harder to make that request if the main thing they have learnt about their inheritance is that they should apologise for it.
That isn't an argument for concealing anything. Understanding a wrong doesn't require inheriting personal guilt for it. Appreciating an achievement doesn't require claiming personal credit either.
We can recognise that Britain participated in the slave trade and later fought to suppress it. We can study liberties developed here alongside the denial of liberty elsewhere. The relationships between those histories deserve explanation, rather than a favourable chapter followed by an unfavourable one to make the totals look balanced.
I would like young people to know enough to feel attachment without having to defend a fantasy. That means giving them the history in its complexity, and trusting them to understand more than a choice between pride and shame.