Although researchers have argued that textbooks should be customized to local cultures and experiences, they rarely are. Ciencia Puerto Rico, a non-profit group interested in promoting science literacy and education among Latino(a)s/Hispanics, identified a need to provide schools with culturally relevant materials. The result was the publication of the book "¡Ciencia Boricua! Ensayos y anécdotas del científico puertorro," an anthology of short, multidisciplinary science essays written by Puerto Rican scientists to develop awareness of Puerto Rican science and scientists. The purposes of this manuscript are (a) to provide evidence of instances of contextualization and cultural relevance in "¡Ciencia Boricua!," and (b) to determine the extent to which the use of "¡Ciencia Boricua!" and related activities changed the perception toward science of 57 elementary and middle school students enrolled in a public school in Puerto Rico, and which contextualized science activities students preferred. The results showed that the contextualized activities improved the perception about science in many children, particularly boys. Students preferred activities with more interactivity, like presenting their science posters during Closing Night, visiting a science laboratory, and receiving guest scientists at the school. Results showcase a successful strategy for developing culturally relevant and contextualized science education resources.