There are so many situations in which content created by educators might benefit from graphics – handouts, bulletin boards, web lessons, etc. I have read recommendations that suggest bloggers should always include an image in their posts. I do include some screen captures and some photographs, but my personal artistic skills are insufficient to create images in other ways. The Noun Project offers images that are perfect for such situations.
For $20 a year, educators can access a nearly unlimited database of icons appropriate for nearly any imaginable situation. The images are scalable (see Maple leaf in a fall color). You establish your credentials as an educator and respond to indicate how you intend to use the images to acquire the $20 fee (the fee for others is $40). Images can be searched using a browser or software (at least for the Mac).
Mac Noun Project application