Un Mar de Colores · San Marcos, CA
Hydrology & Coastal Resilience — Free in San Marcos
Year-round day-trip field trips for San Marcos Unified School District classrooms across San Marcos and North County.
Un Mar de Colores's Watershed Explorers program brings San Marcos youth into the full watershed-to-ocean story of San Diego County. Day trips and overnight summer cohorts trace mountain streams from Cuyamaca State Park to the coast, returning to Carlsbad Tamarack (11 miles) and Oceanside Pier (13 miles) (closest breaks to San Marcos) for ocean-based lessons. We partner with San Marcos Unified School District and community organizations including California State University San Marcos (student volunteers) and San Marcos Unified School District to recruit from Alvin Dunn Elementary, Paloma Elementary, San Marcos Elementary and other Title I schools. Every program integrates the Tijuana River watershed case study — the only cross-border river in Southern California.
Schedule — San Marcos Program Days
Summer cohorts + year-round school field trips · Completely free
You Might Be Feeling This
- —Citizen science sounds exclusive — you didn't know San Marcos students could contribute to real hydrology databases.
- —Climate change lessons feel hopeless — your teen wants advocacy tools, not another slide deck about polar bears.
- —Kumeyaay water relationships are absent from school curriculum — your child hears about Indigenous history without Indigenous science.
What Changes When Youth Get in the Water
- Tijuana River cross-border case study — honest teaching about pollution, policy, and environmental justice.
- BIPOC-led environmental education — instructors who reflect San Marcos communities, not tourist eco-guides.
- Watershed Explorers overnight summer cohorts trace Cuyamaca streams to San Diego coast — multi-day immersion.
Why We Run This Program in San Marcos
San Marcos is the most diverse inland city in North County, with 37% Hispanic/Latino population and home to California State University San Marcos. Our cohorts travel from Alvin Dunn Elementary and San Marcos Middle to Carlsbad's Tamarack for water programming. CSUSM student volunteers support our program delivery, making this one of our strongest university-nonprofit partnerships.
- Population
- 96,664
- BIPOC residents
- 51%
- Spanish-speaking households
- 37%
- Distance to beach
- 11 mi
Watershed Education in San Marcos — What You Should Know
Teachers in San Marcos Unified School District contact Un Mar to book free year-round field trips — San Marcos classrooms access mountain-to-coast science without PTA fundraising.
Citizen science on watershed field trips lets San Marcos students contribute hydrology data — science with public impact, not disposable worksheets.
Why San Marcos Matters to Our Mission
Cross-border watershed work matters to San Marcos because Tijuana River pollution and coastal health don't stop at a border fence. Our education modules name that reality honestly.
With 96,664 residents, San Marcos is one of the communities where a single free surf cohort can change dozens of lives per season. Our shuttles and school partnerships make distance (11 miles inland) a logistics problem we solve, not a barrier families carry alone.
Local San Marcos Partners & Referral Sources
In partnership with San Marcos Unified School District and local community organizations, we recruit youth from 5+ Title I schools.
School district & Title I partners
- San Marcos Unified School District
- •Alvin Dunn Elementary
- •Paloma Elementary
- •San Marcos Elementary
- •San Marcos Middle School
- •San Marcos High School
Community partners
- ◆California State University San Marcos (student volunteers)
- ◆San Marcos Unified School District
- ◆Boys & Girls Club of San Marcos
- ◆San Marcos Library
Program Curriculum
The Watershed Explorers program is Un Mar de Colores's flagship environmental education offering. Summer overnight cohorts trace the journey from Cuyamaca Rancho State Park's mountain streams to the San Diego coast, with special focus on the Tijuana River watershed — California's most cross-border and pollution-impacted river system. Curriculum integrates hydrology fundamentals, Indigenous Kumeyaay perspectives on water, and California coastal policy. Year-round day trips serve school field-trip groups across our 15+ Title I partner schools, and all programming is free with transportation included.
- →Hydrology fundamentals
- →Cuyamaca to coast watershed tracing
- →Tijuana River cross-border watershed case study
- →Indigenous Kumeyaay relationship with water
- →Climate change and coastal resilience
- →Policy and advocacy for clean water
What's Included — Free for Every San Marcos Youth
- ✓Overnight summer program option (Watershed Explorers)
- ✓Day-trip school field trips throughout the year
- ✓Bilingual curriculum materials
- ✓Transportation from partner schools
- ✓Certified naturalist educators
- ✓Family engagement opportunities
Why Un Mar de Colores
Our impact is measured in youth served, school partnerships, and watershed stewardship hours — published annually in our impact reports at mar-de-colores.org.
What our community says
“"He used to approach new activities with extreme anxiety — to the point where sometimes we couldn't even get out of the car. Now he goes much deeper into the water."”
Frequently Asked Questions — Watershed Education in San Marcos
Can San Marcos Unified School District teachers book field trips from San Marcos?+
Yes — we partner with 15+ Title I schools for year-round day-trip field trips. Teachers contact Un Mar to schedule NGSS-aligned hydrology, climate resilience, and advocacy modules with transportation included for San Marcos classrooms.
What ages can join watershed programs from San Marcos?+
Watershed Explorers overnight cohorts and field trips serve all ages — school field trips align to classroom grades, and family engagement opportunities welcome multi-generational San Marcos households.
Can families from San Marcos participate beyond school trips?+
Yes — family engagement opportunities include overnight orientation sessions and select field days. Watershed literacy extends to San Marcos households, not only classroom students.
Are watershed education in San Marcos really free?+
Yes. All Un Mar de Colores programs in San Marcos are 100% free — including 3/2mm wetsuits, soft-top surfboards, transportation from partner schools like Alvin Dunn Elementary, Paloma Elementary, San Marcos Elementary, and certified bilingual instruction. Funding comes from the San Diego Foundation, community grants, and individual donors. No San Marcos family has ever paid for our programming.
Where exactly do watershed education happen in San Marcos?+
San Marcos is 11 miles inland from the coast, so our cohorts are shuttled to Carlsbad Tamarack (11 miles) — our nearest Un Mar teaching beach. Classroom components including curriculum, cultural arts, and tutoring happen at California State University San Marcos (student volunteers) and partner schools inside San Marcos.
What ages can enroll in San Marcos?+
We serve youth ages All ages. In San Marcos specifically, our recruitment runs through San Marcos Unified School District — with priority enrollment for students from Alvin Dunn Elementary, Paloma Elementary, San Marcos Elementary and 2 other Title I schools. Cohorts are age-appropriate (One Ocean for 6–12, Ocean Stewards for 13–17).
Does my child need to know how to swim before starting?+
No. We begin every cohort with ocean-safety fundamentals in chest-deep whitewater at Carlsbad Tamarack (11 miles), supervised by instructors certified by the San Diego Fire-Rescue Lifeguard Division. Water comfort is built progressively. In San Marcos, we also run pre-cohort pool-familiarization sessions at inland pools via our California State University San Marcos (student volunteers) partnership for students who request extra comfort-building.
Are lessons taught in Spanish in San Marcos?+
Yes. All Un Mar de Colores programs are bilingual — and in San Marcos, where 37% of households are Spanish-speaking, we intentionally pair at least one bilingual coach to every session. Cultural programming is delivered in both languages, and parent communications are always sent in Spanish and English.
How is Un Mar de Colores different from other watershed education in San Marcos?+
Three ways: (1) everything is free, while most San Marcos surf programs charge $50–$150 per lesson; (2) we are BIPOC-led and our coaches reflect the 51%-BIPOC San Marcos community we serve; (3) our curriculum includes environmental justice, Kumeyaay coastal history, and cultural arts — not just surf skills. We exist because the ocean should belong to everyone in San Marcos, not just those who can afford access.
How do I sign my San Marcos child up?+
Visit our sign-up page or contact us directly. Priority enrollment goes to students of Alvin Dunn Elementary, Paloma Elementary, San Marcos Elementary and referrals from California State University San Marcos (student volunteers) and San Marcos Unified School District. Summer cohorts fill 3–4 weeks before start, so early contact is recommended.
Ready to Get in the Water?
Support the movement or enroll your youth — Un Mar de Colores is building coastal access for San Marcos families.
All Un Mar de Colores programs are free for San Marcos youth. Reach out to enroll, volunteer, or support the movement.
Un Mar de Colores is a BIPOC-led 501(c)(3) nonprofit based in Oceanside, California. We provide free surf, ocean, and environmental programming for youth across San Diego and Tijuana — bridging cultures, coasts, and communities since 2018.
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