In 50 years, the achievement gap has been unchanged, with the poorest 10 percent of students performing three to four years behind the wealthiest 10 percent of peers, finds a new study in the journal Education Next.
Researchers analyzed performance gaps between the wealthiest and poorest students who participated in four national or international tests taken from 1954 to 2001.
Academic performance improved for 14-year-olds over the years, but the gains faded for 17-year-olds. Income-related achievement gaps stayed flat during that time, translating to about 2.5 years less learning for students among the poorest 25 percent of test-takers versus the wealthiest 25 percent.