Cancer health disparities are often described as the unequal burden of cancer deaths in one racial/ethnic group compared to another. For example, national cancer statistics in the USA shows that Blacks die the most for 9 of the top 10 cancers in men and women. When asked about the underlying causes for this disparity, teen participants speculated that it is primarily due to genetics or biology. This speculation appears to be based on a false concept of 'race.' A science activity was created to counter the false concept that genetics/biology underlie the categorization of humans into different 'races.' This activity provided teen participants with first-hand evidence of how they are all related at one genetic locus, and how they are more genetically related across racial/ethnic groups than within them. Results of surveys given before and after the activity show that they change their perceptions of 'race.' Before the activity, they view themselves as most related at the genetic level to 1-2 well-known individuals (i.e., celebrities) who they perceive as members of their own 'race' mainly because of similar appearance. After the activity, they view themselves as related to more/all the celebrities or they state that they do not know to whom they are most related. This increased awareness of the uncertainty between the apparent 'race' of an individual and their genetics drives teens to dismiss genetics or biology as the primary cause of racial/ethnic disparities in cancer outcomes. Instead, they consider the unequal distribution of the social determinants of health as the primary cause of cancer disparities.