The Lowe's Build and Grow Workshops are offered a couple of Saturday mornings per month and they are completely free. Kids can attend, with their parent, and build something to take home. One week it might be a bird house and another a truck. But they get to learn how to build things and it's a great way to get them actively engaged in a project.
The details vary each month about what is being built. You can visit the site here to get more information each month and sign up for the workshop.