There is Loup Garou, north of Chef-Boutonne which is a youth holiday centre and that has lots of activities in the school hols such as archery, water sports etc
I also saw recently a go-cart that has special wheels to make it an all-terrain vehicle and that was in the Deux-Sevres but I can't find the link at the minute. If anybody finds/knows it please add the website address.
Other than that you have the rivers and lakes for boating and walking - bit cold at Easter for swimming....