This informal learning research project examined how guided participation processes support the use of cultural tools (such as scientific equipment) during a nature walk at one nature center. This paper analyzed family interactions outdoors using microethnographic methods. An informal learning framework based on guided participation and cultural tools allowed for an in-depth investigation of social facilitation used by a working class family: a grandmother, a mother, and two young sons. We identified three findings related to guided participation strategies that facilitated the use of cultural tools for this family, which are discussed in detail: (1) one guided participation process that emerged was the facilitating physical movements related to cultural tool use; (2) a second guided participation process that emerged was balancing the access to cultural tools to reflect family goals for both social harmony and supporting science interests; and (3) trail-based designed learning settings where outdoor explorations occur are important, but understudied, sites of learning for rural families. Implications of the study included the analytical importance of the constructs of cultural tools, guided participation, and embodied science knowledge for advancing research on family learning related to biology and environmental sciences. The research also suggested an expanded view of what counts as an informal science learning institution by including nature trails and related outdoor spaces alongside museums, science centers, and zoos in order to represent the everyday learning activities of rural families.