There is a number that you can call in the website to inquire about large groups. There is also a reservation where your may be able to get free admission for a school group. http://www.ncaquariums.com/roanoke-island-groups
Schools can typically get special discounts. They should have all that information on their website. Also, you should call to find out what kind of special events they might have for large school groups. I don't think the price per kid would be the same as a family going for fun.
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