Two 10-year-old Porirua girls burst into tears when they went on a school trip to the movies because they had no idea the cinema would get dark.
Experiences outside the classroom were "priceless" for Cannons Creek primary school children, but principal Ruth O'Neill said the cost was a huge barrier.
In the past year, the number of pupils taking part in zoo, art gallery, museum and park trips has decreased by 140,000 - down more than a quarter on the previous year.
The Ministry of Education said those figures provided to MPs were not final and that the gap was actually likely to be about 40,000 fewer, as more data was still to be collected.
But Mrs O'Neill said school trips were increasingly unaffordable, and that would cost children in the future. "We asked our year 5 and 6 children who had been to Te Papa or the Botanical Gardens and none of them had. Most of them hadn't even been to Wellington."
School trips provided context to the curriculum, but if children did not have the experience they would always be behind, she said.
Lakeview School principal Ed Hodgkinson said it tried to include everyone when it came to activities, but cost could be a real deterrent. Even with fundraising, trips could be expensive, and staff were left with a "moral dilemma" of deciding whether to let pupils go if they had not paid.
Labour education spokesman Chris Hipkins said inequality should not be an excuse for children missing out on "rich experiences".
Those children with parents that can afford to take them on weekend activities should not have an unfair advantage. "Kids gain so much from learning outside the classroom, yet official statistics just released show that the number of kids taking part in those programmes dropped by over a quarter in the past year. That's a crying shame."
Ministry of Education acting deputy secretary for student achievement Karl Le Quesne said the figures provided to MPs - of 463,915 student visits last year, compared with 323,515 this year - were not final because not all schools had provided their data.
- The Dominion Post
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