We address regional chytridiomycosis through an effective citizen-science program. Ecoclub youth (4-16 years) and families assessed prevalence and distribution of Batrachochytrium dendrobatidis among amphibians of Humboldt Bay National Wildlife Refuge (HBNWR) and Redwood National and State Parks (RNSP), Humboldt County, California (USA). Following required educational workshops with professional biologists, 25 youth and 24 supervising adults sampled 154 metamorphosed amphibians by skin swabs and 15 tadpoles by buccal swabs, May 2013 through December 2014. Using real-time polymerase chain reaction tests, 30/169 (18%) samples were positive for B. dendrobatidis, including 8/68 Pacific chorus frogs (Pseudacris regilla), 3/22 Western toads (Anaxyrus (Bufo) boreas), 3/25 northern red-legged frogs (Rana aurora), 16/26 foothill yellow-legged frogs (Rana boylii), 0/3 ensatina (Ensatina eschscholtzii), 0/2 California slender salamanders (Batrachoseps attenuatus), 0/5 coastal giant salamanders (Dicamptodon tenebrosus), 0/3 rough-skinned newts (Taricha tenebrosis), and 0/15 tadpoles. At HBNWR, fewer [6/73 (8.2%)] metamorphosed amphibians were positive, compared to RNSP [20/69 (29%)], and the workshop training wetland [4/12] (Chi2=10.36; p=0.0056). Median chytrid zoospore intensity among positive samples was 1.7 (range: 1-33). Fifteen of 75 (20%) amphibians sampled by youth <12 years old were positive; similarly, 15/94 (16%) amphibians of participants >12 years of age were positive. Except for Rana aurora, all are first-time species reports for Humboldt County. These findings were comparable to other regional chytrid studies, supporting the potential value of involving children and families in citizen-science projects. The project incorporates traditionally underserved communities: 10 of 25 participating students have Latino heritage, Native American heritage, and/or African-American heritage. Socioeconomically, about half of all families in the school district fall below 130% of the federal poverty guidelines. Besides addressing a pressing wildlife health issue, direct participation of Ecoclub youth and families in this research contributes to science education among a multigenerational public and encourages broader stewardship.