Particles and populations: two ideas students often get wrong
· 2 min read
Two of the biggest ideas in school science, that matter is made of particles and that populations change through natural selection, are also ideas students often get wrong.
What the research found
- The particle nature of matter. Nakhleh’s review of chemical misconceptions describes how students’ ideas about core topics such as the particle nature of matter often differ from accepted chemistry, and what that means for teaching.
- Natural selection. Bishop and Anderson found that many students in a college non-majors biology course thought traits change because organisms need them, overlooking variation within a population.
These studies are about how students learn science, not about SubjectPath.
Why it matters for diagnosis
A student can hold one of these ideas and still give an answer that looks right. Answer choices written to reveal those ideas help a diagnostic tell them apart.
How SubjectPath will apply this idea
The Chemistry and Biology Paths are coming soon. They will be built on the Next Generation Science Standards (NGSS), and their answer choices will be written to reveal misconceptions like these, so practice can start where understanding breaks down.
What a diagnostic can look for
Take natural selection. One answer choice might say a population changed because individuals needed a trait. Another might say individuals with the trait survived and reproduced more often. Both use the vocabulary of evolution, but only one matches the accepted science. Answer choices written this way let a diagnostic tell a student’s actual idea apart from familiar words.
Why these two ideas
Matter and natural selection sit underneath a great deal of later chemistry and biology. A student who misunderstands either one may struggle with the topics that build on it, which is why the ideas students bring to them are worth finding early.
Sources
- Nakhleh, M. B. (1992). Why some students don’t learn chemistry: Chemical misconceptions. Journal of Chemical Education, 69(3), 191–196.
- Bishop, B. A., & Anderson, C. W. (1990). Student conceptions of natural selection and its role in evolution. Journal of Research in Science Teaching, 27(5), 415–427.