Purpose: Curriculum supplementation by teachers is an agelong tradition, and the widespread use of the internet has increased the use of online resources in the classroom. This paper aims to explore preservice teachers' views on multicultural science resources and make a case for the representation of the changing demographics of the American classroom in online resource development. Design/methodology/approach: Using a qualitative interpretive approach, this study explored the perceptions of preservice teachers on their access to and use of online science resources through the conceptual lens of the pedagogical design capacity framework (Brown, 2009) and the first two principles of critical and cultural approaches to ambitious science teaching (C[superscript 2]AST) (Thompson et al., 2021). Findings: Participants in this study have not accessed culturally relevant online science resources. They adapt the resources to meet the demographic needs of their class. Practical implications: This study aims to support the need for content creators of online educational repositories to develop multicultural science resources. Originality/value: This work not only gives a background to why preservice early childhood science teachers could not access multicultural online resources, but it also makes a case for integrating skills needed for teachers to create culturally relevant resources into teacher training programs.