Historically the Marshallese population was taught in English first with Marshallese instruction coming later, but this was reversed in the 1990s to keep the islands' cultural heritage and so children could write in Marshallese. Now English language instruction begins in grade 3. Christine McMurray and Roy Smith wrote in ''Diseases of Globalization: Socioeconomic Transition and Health'' that this could potentially weaken the children's English skills.