As English-only efforts continue in the US schooling system, dual-language programs have served as attempts to preserve students' home language. An after-school, dual-language, Spanish-English, mathematics program, Los Rayos was developed in a predominantly Mexican/Mexican-American neighborhood in Chicago. As participant observers with a sociocultural perspective, we explored the linguistic and personal resources used by participating 4th grade bilingual Latina/o students. We found that students used imaginative, playful, and hybrid linguistic resources to make sense of and solve probability tasks when engaged within a zone of mathematical practice. Results challenge narrow perspectives on bilingual students' linguistic resources. Language implications are discussed.