He returned to the United States in 1877 for further first-hand research on school systems. He spent considerable time at Amherst College and approached Amherst president Julius H. Seelye for advice. He also visited the Centennial Exposition in Philadelphia, after which he submitted a report with photographs to the government. On his return to Japan, Tanaka strongly criticized the Education Order of 1875, which he felt made the system too centralized and inflexible. The new Education Order of 1879 was based on his experiences in the United States, but it quickly came under attack as being confusing and inviting moral decay. Tanaka transferred from the Ministry of Education in 1880 to the Ministry of Justice, and subsequently served in various positions in the Meiji government.