We all come in different shapes and sizes, and yet, especially lately, with all the emphasis on childhood obesity, we want to have a gauge for what is normal. Normal is different than average, and that is where the confusion comes in. Average is simply what is typical for an age group, but what is normal is much more varied.
Elementary School-Age Children, 5 to 11
When a child enters kindergarten, he or she will typically be 40 inches tall and 39 to 41 pounds. There is, of course, variance, but in the first six years of schooling boys and girls are more alike than different in terms of averages. When reading a growth chart look for consistency. If your child is in the 70th percentile for weight, meaning she is heavier than 70 percent of her peers, look to where she measures on the height scale. It is normal for a child to stay within their percentiles for height and weight. There should not be more than a 10 percent variance in height and weight percentiles. In other words, if your child is in the 70th percentile for weight, her height should fall in the 60th to 80th percentile. Upon exiting elementary school, most children will be 52 inches and 77 to 79 pounds.
Middle School-Age Children, 11 to 13
In middle school, the girls tend to grow faster than the boys. Upon entering sixth grade, both genders will be about 52 inches tall and within a 2 to 5 pound weight difference. Over the course of the next six years, gender height-weight variance peaks.The average girl will become about 10 pounds heavier than her male peer and up to 5 inches taller, and this is at the average 50th percentile mark. The variance can be 10 inches and nearly 50 pounds and still be normal depending on consistency of percentiles (e.g., 30th percentile for height, 35th percentile for weight).
High School-Age Children, 14 to 17,
During the first year of high school, boys tend to catch up to the girls. By age 14 to 15, both boys and girls tend to be at least 63 inches tall and at least 105 pounds. By age 15 to 16 girls are nearly at the end of their growth period, and tend not to grow more than another inch. It's normal for boys at this age to show increased appetites and grow several inches in height and gain several pounds. By age 17 to 18 the normal and expected height for a male is between 5-feet 7-inches and 6-feet, with a weight of between 130 to 150 pounds. Its normal for a girl to gain 10 to 15 pounds between 17 and 18, but not height.
Determing Your Child's Normal Height and Weight
Growth charts are a tool that merely tell you where your child is in comparison to others his or her age. The important way to use this tool is to know your child's pattern. There are many fluctuations in the first two years of life, but by age two your child should consistently stay within his or her height and weight percentile. Falling outside the personal normal pattern is a red flag that something needs to be addressed, whether it be an illness or a behavior modification. Normal is going to run the gamut from high to low, short to tall, depending on genetics, environment, nutrition and health.
Encouraging Normal Height and Weight
Although normal is relative, you can encourage normal height and weight growth for your child. Children who eat the recommended servings of fresh fruits and vegetables, who eat whole grains, and get plenty of protein and calcium from natural sources, tend to thrive. Children need a good 30 minutes a day of activity to maintain health and stave off many of the childhood onset diseases, such as diabetes. A diet rich in nutrients, avoiding processed foods and refined sugars, coupled with exercise and fitness will naturally fulfill a child's personal height and weight norm.