Gradeschoolers discover mammography

Jessica Goldkind* and Ram Srinivasan

*Stanford Teacher Education Program (STEP)

Ram Srinivasan teamed up with Jessica Goldkind from the Stanford Teacher Education Program (STEP) at the Stanford Graduate School of Education to bring mammography physics to the high school classroom. Click here to jump to the lesson plan materials.

Magnification and Mammography

The centrepiece of this collaborative effort is a 60 minute lesson plan, the mammography outreach module (MOM), that Goldkind and Srinivasan developed, allows high school teachers to lead an interactive, experiment-based learning session on mammography physics. The module begins with basic clinical information on the vital role of projection radiography in breast cancer screening. The lesson then guides students through an experiment which allows them to discover and derive the operating principles behind magnification, illustrating tradeoffs between geometric magnification and blurring. Students also learn the basic skills of empirical science, including data gathering, model fitting, and theory. Because Goldkind and Srinivasan wanted this module to be universally accessible to all classrooms, the module makes use of inexpensive items like pen flashlights, popsicle sticks and paper.

Students gather data to establish a relationship between radiographic magnification and source-object distance.

To commemorate the 119th anniversary of Wilhelm Roentgen's discovery of x-ray production and detection, Jessica and Ram taught the science of magnification in mammography as part of the Fall 2014 Stanford Splash Educational Studies Program for grade school students. Over 70 students in grades 9-12 participated in this 60 minute lesson that repeated over four separate sessions and two days. The experience was important for refining the lesson plan, exploring the limits of guided exploration in classes with diverse backgrounds and limited time constraints.

Lesson Plan Materials

  • Worksheet. This 26 MB two-sided PDF, also available in Adobe Illustrator Format (.ai) was printed and distributed to each student at the start of the lesson. The first page introduces the background material, including why we perform breast cancer screening, how projection radiography works, and what the basic mammography unit looks like. The first page also helps teachers frame the basic problem: how do we magnify the image of a calcification to determine if it's benign or suspicious? The second page is a self-contained worksheet for collecting data and performing analysis on magnification.

  • Jessica Goldkind fields questions as students gather data to discover the principle of magnification in radiographic imaging.

  • Lesson Plan. The full five-page lesson plan in PDF or MS Word, led by Goldkind, includes more detailed instructions to teachers in helping them guide the class through these materials. The lesson plan figures can also be downloaded separately in PDF and CorelDraw X6 Format (.cdr).

The class transitions from lecture to hands-on experimentation, after students hear about the basics of image formation in mammography.