IQ–what an elusive subject! What is it? What does it mean? How is it measured? What is a normal IQ? What does “gifted” mean? Where does IQ come from? Does it change over time? Can IQ be improved? Read on, reader.

IQ is a number that represents a person’s ability to make use of knowledge: acquisition, comprehension, storing, analyzing, synthesizing, reasoning, producing, and communicating. There is a long history of debate about the definition of IQ.  Even while the debate continues, psychologists administer standardized tests to measure IQ. What’s being measured? Visual-spatial skills. Speed of thought. Reasoning and inference abilities. Fund of knowledge. Capacity to use “mental scratchpad” to hold and move images and concepts. Adeptness at communicating what you know. Fine motor skills. Common sense. IQ tests define IQ as composed of these many skills…rather than one global ability. But, one overall score is yielded by a mathematical formula that combines many subtest scores.

IQ scores range from below 70 to over 200. Beyond 200, it’s difficult to measure; these are IQ scores of geniuses who can graduate from ivy league schools before they can drive a car. Over 80% of the population has an IQ between 80 and 120. Scores of 80-89 are considered to be in the Low Average range of intellectual functioning. Scores of 90-109 are Average. Scores of 110-119 are High Average. An IQ of 125 is considered by many schools to be “gifted.” Scores of 120-129 are Superior. And scores above 130 are Very Superior. IQ scores are based on a person’s test performance compared to others their age.

This is important: To do well on IQ tests, a child must be engaged, focused, emotionally regulated, and motivated to do well. This means that children with mental illness sometimes do pooly on IQ tests. Does this mean they are “stupid?” Not at all. A child with Asperger’s Disorder, for example, may simply not be motivated to follow the instructions. A child with ADHD may not have the ability to pay attention when necessary. But these kids are often, in the real world, just as smart as their peers. A child can do poorly on IQ test for a number of reasons, but can do well only if she is truly able. Therefore, it is possible for IQ tests to underestimate a child’s intellectual abilities. But, an IQ score can never overestimate a child’s smarts.

An IQ number is handy, especially in academics. While IQ tests do not directly measure a person’s capacity to learn, they do show how well a child is likely to do in school. A child’s IQ score(s) helps parents and teachers form reasonable expectations for a child’s academic progress. IQ scores are the foundation of knowing, truly, if a learning disability is present. (Even though, in Illinois, schools have moved away from using IQ in this way). IQ tests can outline a child’s specific strengths and weaknesses. Although they are not diagnostic (e.g., they do not in themselves show ADHD), IQ tests can point parents in the right direction for next steps in treatment.

How does a child “get” his IQ? Hard to say. There’s a genetic component, linking especially the child’s mother’s IQ to his. There are also very strong environmental correlates to IQ. Love. Diet. Sleep. Safety. These are foundations that help support brain growth. Studies have shown that the amount of brain growth in early infancy is linked to IQ.

IQ tests are available for very young children. There are even ways to guess an infant’s IQ (hint: duration of stare). Standardized IQ tests are available for children as young as 2 1/2. IQ tests are sometimes required for admission into elite or private schools, where tests are given when children are 5 or 6 years old. In the psychology biz, we say that “IQ is generally thought to be stable after about age 12.” This means that whatever score a 12 year old achieves, he is likely to get roughly the same score when he’s 15, 20, 30, and so on. (In middle age, IQ scores tend to change: speed scores go down, knowledge scores go up). Age 12 is the magic number for a child’s cognitive development, the age when he can reason with relative sophistication.

Yet, psychologists know that a child’s IQ can change over time, even after 12. Most times, the change is not significant. A new study found that significant changes do occur, and concludes that changes in IQ reflect changes in ability. Remember that IQ is measured by tests that look for certain things. If a child has been skipping school, he’ll do poorly on parts of the tests that measure fund of knowledge. If she took cold medicine on the day of the test, and is a cognitively “fuzzy,” she may struggle in speed tests. Environmental factors can always play a role in changing IQ scores. But that is not what the researchers are saying. They’re saying that, based on changes in brain development, children’s intellectual abilities change. The sample size in the study was small, but it is an interesting observation.

So, if IQs change  (significantly or not) can you improve your child’s IQ? You can sure help her improve IQ test skills, so she’ll score higher.

• From ages 0-2: Read to your child. Often. Talk to him, using direct and sustained eye contact. Turn off the TV. Don’t buy the “education-based” video games. Love and praise your child. Play music you like for her (it does not have to be classical music). Explain everyday things to him. (Tell her why orange juice can sting a cut on a lip. Tell him why a hot stove must not be touched.) Praise your young scientist for repeating things over and over. Play peek-a-boo and hide-and-seek. Enforce a healthy diet, and try for organic foods if possible. Use routine, with predictable consequences for behavior. Introduce math concepts. Sing the ABCs. Make sure your baby gets enough sleep.

• From ages 2-7, a child should be exposed to new things-music, sports, subjects, activities. Keep reading aloud to your child, and praise her efforts to read to you. Talk to your child about why people behave as they do. Who makes the rules in society? Why? Buckle down on homework, establishing high expectations for work habits. Extra work (school worksheets during summer) is recommended in reasonable doses. Homework should not be a fight. If it is, talk to school teachers or a child psychologist. This is the age that learning disorders can start to show. Get a handle on them early. If you have the opposite issue–your child wants to learn more than you can possibly teach–try to connect her to an expert in her field of interest. Perhaps a college professor would be willing to tutor your child for a couple hours on a weekend. Schedule playdates. Continue healthy sleep and diet activites. At this age, children are scientists. Conduct fun and interesting household projects that help your child explore their world. Play guessing games such as, “I spy”, and “I’m thinking of something…” Do puzzles and card games.

• Children 8-12: Encourage independent reading and books-on-CDs. Enforce healthy sleep and diet. Limit TV and video game time. Be an active participant in your child’s academics, remembering that you are doing him no favors by completing homework for him. Teach work skills, including: organization, time management, scheduling, focus. Praise your child for good report cards, but avoid monetary rewards for them. The goal is to help your child internalize the value of good grades, and not simply work for an external reward. Use intermittent reinforcement. Listen to teacher’s feedback about any problematic academic or social behaviors. Listen to your child. Encourage her to pursue her intellectual passions (which may not be theoretical physics or advanced mathematical theory). Institute a “family game night,” where you play cards, puzzles, or other games that help build reasoning skills. Introduce your child to newspapers and have easy chats about what is happening in the world. Talk about governments, nationalities, and cultures. Explain real-life issues like, “why do we keep our money in a bank?” “what should you do if a bully picks on you?” and “why does the guy from the gas company read our meter?”

• Ages 12-18: Children become increasingly independent. The foundation for IQ is already set, but test performance can improve for some children. There is no substitute for attending school regularly, paying attention in class, and doing homework. These are musts. Keep a close watch on your child’s use of electronics. Phones, video games, and computers can interrupt sleep, cause social disruption, and distract children from work. Help your child link her academic performance to her long term goals. Consider hiring a peer tutor, someone your child can actually tolerate. Help your child continue to build work skills such as organization, time management, avoiding procrastination, and breaking down big assignments into small “do-able” parts.

Our kids may not become Albert Einsteins or Stephen Hawkings, but they can learn and improve skills that help them get higher IQs.