See above.Quote from VOA:
Staying in school really can make you smarter. A new study by researchers in Norway have found that students who remain in school longer than other students the same age have higher IQ scores.
In the mid-1950s, the Norwegian government began requiring students to attend school until they were 16 years old, rather than allowing them to drop out at 14.
Communities had until 1972 to phase in the compulsory education reform, which meant that, for nearly 20 years, youngsters in some municipalities went to school for seven years and others attended classes for at least nine years.
That gave Taryn Ann Galloway a unique opportunity to see what impact the extra two years of education had on the intellectual development of students.
The average IQ score on the intelligence test is 100, with most of the population falling somewhere between 85 and 115 on the scale.
For years, there's been vigorous debate among psychologists about whether a person's intelligence is the result of "smart" genes or a nurturing environment in infancy. Galloway's results seem to support the nurturing side of the nature versus nurture argument.
She suggests getting two extra years of academic practice during the middle teenage years may also help boost IQ scores.
"I think it's because you do learn general thinking skills at school and you are able to practice them, and you have lots of opportunity to practice them. So this is a two year extension of compulsory schooling for two years, so they were able to simply improve their skills."
We don'tDon't we need to put "at" before "the same age"?
No, we don't. It's a shortened form of "other students who are [of] the same age".
2. Which one is correct, "on the test" or "in the test"?
They're both possible.
3.I don't understand this sentence.
There is an ongoing argument about whether people turn into the adults they do based on a natural tendency (nature), or because of how they are brought up (nurtured). This is the "nature versus nurture argument". The writer is saying that the evidence from the school experiment supports the "nurture" side of this argument.
setnencesentence sound redundant?
Certainly some of it does. It repeats the phrase "two year(s)".
Student or Learner