Mariposa Subdivision and the Rio Rancho School District January 8, 2007: Mariposa is annexed into the Rio Rancho School district. The state has approved moving thousands of acres in the northwest part of the city into the Rio Rancho school district. $300,000-$400,000 homes are being built at Marioposa right now. The development is expected to eventually have 6,700 homes and 400 commercial uses over a period of 15-25 years to complete. Source: ABQ Journal and Rio Rancho Observer Monday, Dec. 12, 2006: RR School Board approved to annex Mariposa into the RR School District. Formal approval is still needed to make the decision official by the Public Education Department.