I've never had anything on my classroom walls that attracted my students and coworkers (and administration!) more than my meme wall. This wall created interest in my content from day one in my classroom, spurred questions from students, and helped establish memorable rules.
On multiple occasions, I have had students apply the rules from my meme wall on their assignments. For example, I have my students write one to two sentences, defending their multiple choice test answers. Frequently, my students use the memes hanging up in my classroom as their defense.
This PDF includes 32 memes to be used as posters in the classroom or files to spark some interest in a PowerPoint, etc.