Mexico's Yucatán Peninsula is a karstic limestone plain so permeable that precipitation passes directly into the porous ground. Surface contamination travels with this water into a subterranean network of fissures and then toward the coasts. Agriculture, industry, tourism, and households all contribute to the contamination. The first to suffer are those who drink the water. Scientists have long understood the situation, but that information has yet to be fully translated into policy or public awareness. In the United States, scientists and educators face similar challenges promoting water stewardship and have developed several tools in response: (1) It has been found that young people can be effective communicators on environmental issues. (2) Groundwater demonstration models help the public visualize the dynamics of water. (3) Simple and rapid water analysis kits enable adults and young people to engage with water quality in their communities. In concert with other Mexican educators we introduced these teaching tools in technical high schools in Yucatán State in 2012–2013. The students engaged with the public using groundwater demonstration models we adapted to the Yucatán Peninsula. Five schools formed a water monitoring network similar to U.S. citizen monitoring networks like IOWATER. Participants gained an understanding of the nature and extent of water pollution, and they learned that they can use science to help their communities. Scientist–educator linkages were strengthened.