They may know their science, but some young students have not mastered the art of providing the answers that teachers look for in exam scripts.
They end up using the wrong words, even when they know the correct answer. This is because they may not have grasped the precise nature of scientific language.
A National Institute of Education (NIE) researcher is trying to fix this problem, which has long been a challenge in learning primary school science.
Dr Seah Lay Hoon, a research scientist, started two projects in 2013 and this year, to see how teachers view students' language- related challenges in science.
The studies are funded to the tune of more than $170,000 by the Education Ministry.
Dr Seah has written two papers based on the earlier study. Her first paper on the challenges that primary school pupils face in learning scientific language was published in the international journal, Research In Science Education, in March.
The second piece, on how teachers perceive science language issues in classrooms, will soon be published in the International Journal Of Science And Mathematics Education.
For the first project, ending in July, she interviewed nine primary school science teachers and observed their lessons over six months. She also analysed written answers given in a science test by four classes of Primary 4 pupils.
Her second project, which began this year and will last until the end of next year, involves in-depth interviews with five secondary school teachers, and planning lessons with them.
Her initial observations are that teachers tend to focus on content and neglect language, given constraints such as time in the classroom.
Teachers do not always convey to students "how language in science has distinctive features, and is different from everyday English", she said.
For instance, saying that a balloon is "inflating" or "expanding" may project the same image of a balloon becoming bigger, she said.
"But inflating gives you a more precise meaning because you know that something is entering the balloon, so that it expands."
She is now developing lesson strategies with teachers to help students learn science better.
This includes helping students to identify scientific concepts such as "cause and effect" or "compare and contrast".
Other ways include getting "wrong" answers from students through games at the start of lessons, before teaching them the right ones, so that they understand why the correct answers are better.
This could help students tackle open-ended questions better, said Dr Seah, a former secondary school science teacher who taught chemistry from 2000 to 2002.
Agreeing, Associate Professor Manu Kapur, who is head of research at NIE's Learning Sciences Lab, said: "If you go prematurely into teaching keywords, that's not good. Kids don't learn well if they're just told, 'You cannot use this term or that term.'"
The issue of precise language in science was raised when several parents wrote to The Straits Times Forum page in February.
They said their children were unduly penalised for answers that had the same meaning as the correct ones, but did not contain the right "keywords".
Dr Seah acknowledged that some teachers may be stricter than others in marking, but stressed that scientific language demands precision.
When asked how a lion was different from a bird, for instance, stating that "a bird has feathers but a lion does not" may not be enough, as students need to compare both animals' outer coverings, she noted, adding that the better answer would be "a bird has feathers but a lion has fur".
Ms Elizabeth Tan, whose son is in Primary 6, said the studies will be useful in helping teachers understand how students think.
"But, in reality, teachers are under pressure to finish content and make students score better, so the easiest way is to teach keywords," said the 41-year-old housewife.
This article was first published on May 5, 2015.
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