The SPAN lab team hosted a class of 4th graders from Jackson Elementary School on Friday, Dec. 11. The 4th graders learned generally what electrical engineers do, and specifically, the mathematics and engineering of tomography. Tomography can be explained as finding numbers to solve addition problems, and the class worked on finding images given their row and column sums. Then, they conducted experiments using the radio tomographic imaging testbed. We thank the Adelante program and the students who visited for spending their time with us. Our tomography activity plan, slides, and worksheets are posted, along with photos from the event.