Eva Longoria tells PEOPLE she was inspired by the volunteers who worked with her family and helped her older sister, Liza, who was born with an intellectual disability

Before she portrayed a Desperate Housewife, Eva Longoria had a very different career in mind.

Growing up, Longoria, now 44, says she was inspired by the volunteers who worked with her family and helped her older sister, Liza, who was born with an intellectual disability.

“We kind of grew up in her world and that meant volunteering a lot, and that meant knowing community programs and it just meant giving back to people we never knew, people we never met, and receiving from people we never knew and people we never met,” the Desperate Housewives actress tells PEOPLE.

She continues: “I always wondered, ‘Who are these people helping our family with this program or that class?’ And my mom would explain they were philanthropists. So I knew that word very early on in my life and that’s what I wanted to be. I said, ‘I want to be a philanthropist when I grow up.’ ”

Though Longoria dreamed of helping people, she couldn’t predict having the reach she does have today. “When Desperate Housewives exploded globally, I thought, ‘Here is such an opportunity to say something. So what are you going to say?’ ” she says.

She decided to focus on a cause that spoke to her identity: Latina women.

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Credit: Eva Longoria Foundation

While pursuing a master’s degree in Chicano Studies from California State University, Northridge, Longoria’s vision became even clearer. “I wanted to focus on education, but [my mentor] drilled it down even further,” she says. “ ‘But what about education? Where? Pre-K and college? Where do you think the greatest intervention is?’ ”

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A study she commissioned with UCLA revealed a startling lack of Latinas in STEM (Science, Technology, Engineering and Math) fields. So she launched the Eva Longoria Foundation in 2012 to help close this gap.

Her foundation provides Latinas with entrepreneurial training and education support, powered by the $3.7 million they’ve raised to help Latinas with STEM education.

“My hope is there’s no need for the foundation in 10 years,” she says. “Philanthropy and foundations are supposed to catch people who fall through the cracks that the system really didn’t work for. … I wish we didn’t need the foundation to catch those people, but I hope that through our participation in politics and our participation in communities, that we will change that.”

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Eva Longoria
| Credit: Ramona Rosales

Longoria — who has directed and produced more than 20 projects collectively — is also committed to giving Latinos better opportunities both in front of and behind the camera.

She’s a passionate advocate for voting rights and a founding member of Time’s Up.

“It’s created this sisterhood among my peers and colleagues in the industry,” she says. “We’re breaking out of the mold they created where there’s only room for one woman at the top … and breaking that mold has been so liberating for us.”

The birth of her son Santiago, 20 months, who she shares with husband José Bastón, has given Longoria’s work a new urgency.

“I’m making sure that this world is a good place for him to grow up,” she says.

Next, Longoria will direct and star in the workplace comedy 24-7 alongside Kerry Washington. She will also direct Fox Searchlight’s FLAMIN’ HOT, a biopic about Richard Montañez, the son of a Mexican immigrant who started out as a janitor at the Frito-Lay factory before creating the spicy Flamin’ Hot Cheetos and becoming a wildly successful businessman.