WP Clipart is a public domain clip art site with almost 25,000 images for projects that are “safe …for children and others to find good-quality, printable images that have no copyright restrictions.” The pictures are arranged by category and instructions are included for downloading. Even though the site says pictures are good for inkjet printing, I don’t see why classroom laser printers can’t be used. If you have any questions regarding license and copyright, please click here for information.
