Final answer:
Without specific information about Joe, it's not possible to determine what high school he moved to Seattle to attend. Seattle's school assignment system aimed to promote diversity and allowed parents to choose schools across the city.
Step-by-step explanation:
The question does not provide enough specific information on Joe's high school in Seattle; however, relevant context around Seattle schools can be discussed. According to the Supreme Court cases mentioned, Seattle had a school choice system that was designed to promote racial diversity. Parents in Seattle could choose any school in the city for their child's education. When the demand for a particular school exceeded the available spots, priority was given to maintain a racial balance. Determining which high school Joe moved to Seattle to attend cannot be accurately answered without additional information about Joe himself.