1、ATesting Theories of WhyFour Keys to Interpreting US Student Achievement TrendsA M E R I C A N E N T E R P R I S E I N S T I T U T ENat MalkusJANUARY 20251Executive SummaryAlthough national test scores provide clear evidence on student achievement across time,they do not illu-minate what is driving

2、gains or losses.Nonetheless,careful examination of test scores can corroborate some explanations for changes in student achieve-ment and discount others.This report examines recent trends in US student achievement,as measured by national and interna-tional assessments,and identifies four key trends

3、that any satisfactory explanation of recent US student performance should account for:a downward trend beginning around 2013;declines driven by the bot-tom half of the distribution,both before and after the pandemic;higher absolute achievement gap growth in the US than other nations;and adult assess

4、ment trends that closely match those of students.The report concludes by evaluating how common expla-nations of student achievement trajectories align with these trends.2Testing Theories of WhyFour Keys to Interpreting US Student Achievement TrendsNat MalkusOnce or twice a year,a familiar sequence o

5、f events repeats itself:A new round of national test scores are released.The results make the news because they are new and because test scores are important.And then gallons of ink are spilled arguing why scores changed as they did.Its cable TV,or MTV,or vio-lent video games,or the internet,or the

6、phones.Its the teachers unions,or the parents,or the inaction of policymakers,or the meddling of No Child Left Behind.Its the advent of MySpaceno,Facebookor Instagram,definitely TikTok.Its the obesity epi-demic,the loss of recess,the overemphasis on sports,the shriveling of arts and music,or the lac