ABC Graffiti is a great resource for the beginning of a unit or as review! I've used this activity several times and the kids love searching for words that fit!
For example, I used this activity in a 8th grade classroom most recently. We were beginning the Civil War and students could only use their text books. For the letter A, students would write down Abraham Lincoln. OR they could use it for L because of Lincoln. For B, they used bombardment and tied it back to Fort Sumter. For X-Y-Z, the students only have to find one term.
This is great for all content areas and all grade levels! Let me know how it goes in your classroom!
*** In the thumbnails I included a few examples. Examples include: The Civil War, The Great Gatsby, and Ecosystems.