DocsTeach is one of my favorite tools for building history lessons centered around primary source documents, pictures, maps, and drawings. DocsTeach contains an integrated search tool for finding artifacts from the U.S. National Archives. You can use that search tool to find political cartoons. That was focus of a recent professional development webinar that was hosted by the US National Archives.
Teaching the Constitution With Political Cartoons is now available to view for free. The webinar focuses on using Clifford K. Berryman cartoons from the U.S. Senate Collection in lessons designed to help students understand the nuanced aspects of the US Constitution. The webinar includes a good overview of how students should analyze political cartoons and guiding questions that you can give to your students. The last third of the webinar, around the 27 minute mark, is where the webinar transitions into demonstrating how to use the tools within DocsTeach.
The webinar recording is available here and as embedded below.
Untitled [Political Cartoon]; 3/24/1937; (Y-086); Berryman Political Cartoon Collection, 1896 - 1949; Records of the U.S. Senate, Record Group 46; National Archives Building, Washington, DC. [Online Version, https://www.docsteach.org/documents/document/passing-the-buck, November 30, 2018]