Footage shows several pupils running for cover as the huge vessel hit the water and unleashed a powerful wave.
One student filmed as two of his classmates were knocked off their feet by the surge as it rushed across the grass.
A split second later, the cameraman was also bowled over.
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The pupils from Dr Aletta Jacobs College in Hoogezand, Netherlands, had gone to the edge of the Winschoterdiep canal in Foxhol on 5 June to watch the launch of the NB 758 cargo ship up close.
But they quickly regretted picking such a prime vantage point as the 90-metre vessel slid into the water and triggered the enormous wave.
Seconds before they were swept off their feet, one pupil could be heard shouting the infamous last words: “There won’t even be any water, man.”
Fortunately, the damage was limited to a few water-damaged phones and one bruised ankle, as reported by Need To Know.
Devin, 13, was one of the pupils filmed being knocked over by the wave.
He joked the next day: “Luckily I’ve dried off a bit now.”
Mohamed, 15, had been standing at a safer distance and watched his classmates get engulfed.
He said: “I couldn’t stop laughing for five minutes, I almost had stomach ache.”
Charomy, 13, said: “When I saw the water coming, I wanted to run, but I kind of fell. And then it was already too late.
“People came up to us asking if we were okay, that was really kind.”
Luckily, the soaked teens were allowed to go home to shower and change before returning to class.
“And thank goodness, because that water was really dirty,” Charomy added.
Their teacher Paul, who had warned them in advance about the risk, later showed the footage in class.
Divina, 14, said: “He laughed at us really hard.”
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