Ayscoughfee Hall School in Spalding is seeking planning consent to replace windows in a 20th century, prefabricated classroom block.
The school, in London Road, also wants to provide a new, single storey. “infill” extension and a link covered way.
None of the changes directly involves the main building, Welland Hall, which was built as a grand, three-storey house in the mid 18th century.
Architects for the school say the work will involve “the concealing of the prefabricated concrete panel annex with materials that are more sympathetic to the site”.
South Holland District Council will decide if the building work can go ahead.
• Gosberton Academy Primary School will extend its dining hall to create a table store if the council consents to plans submitted by Cotts Builders and Contractors.