The Mystery of Wickworth Manor by Elen Caldecott

Bloomsbury, 2012. ISBN 978 1 4088 204803.
On a school camp to Wickworth Manor students from a variety of schools are thrown together.
Paige is a bright student with leadership qualities who arrives on a bus load of children and Curtis is a shy reclusive student whose mother drops him off at the manor . As their surnames end in the same letter they are roomed on the same floor. On the first night Curtis seeking some solitude stumbles across a small room in which an old painting is stored. Paige follows Curtis and in continuing to explore the room locates a mysterious letter that seems to link the painting to some tragic event many years before. So begins an adventure that sees both students nearly removed from the camp and also uncovers untold stories from the past.
The manor becomes a trove of secrets and mysteries and much of the sleuthing that Paige and Curtis do takes place under the cover of darkness.
Tracy Glover