Science is always advancing—but kids still need to start with the basics, from how animals are born to the way electricity flows.
The National Assessment of Educational Progress, which measures students’ science knowledge, tests those topics and more—and the most recent results show that U.S. fourth-graders improved their scores in 2015 compared to 2009, when the test was previously administered. Fourth-graders also erased the gender gap between boys and girls on the science test. Still, just 38% of fourth-graders tested at a proficient level or above, which some say reflects the high standards of the exam.
See how you’d fare on the test, based on these fourth-grade sample questions from the 2009 assessment:

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