Although your child's last vision check may have been normal, it's possible to develop nearsightedness (also known as myopia) at any point during childhood. Myopia can be inherited from parents, so your child is at a higher risk of this if one or both parents are also nearsighted. However, having nearsighted parents doesn't mean your child is certain to be nearsighted. Environment and habits play a part as well, so your child may not develop any vision problems at all. But just in case he or she does, you should be on the lookout for these signs of nearsightedness so you'll know if your child needs an eye exam to check for myopia.

1. Holding things close to look at them

This sign is easy to demonstrate with the example of a book. When your child is reading, does he or she hold the book up near face level? This is not a comfortable position to read in, so a child with normal vision is less likely to hit on it as a viable reading position. You can also observe how close your child sits to the TV; sitting on the rug in front of the TV can be normal behavior for a child, but sitting right in front of the TV screen may indicate developing nearsightedness.

2. Compensating

A child whose eyesight is suffering may develop idiosyncrasies to try and cope with the difficulty in seeing things. For example, if your child is getting nearsighted and you ask him or her to look at a distant object, he or she may squint to try to bring the object into focus. 

3. Eye strain

Eye strain can show up in a number of ways. Basically, it's the result of working too hard to focus with eyes that are suffering from a problem such as nearsightedness. If your child has eye strain, he or she may complain of frequent headaches and seem more sensitive to bright light. Other signs of eye strain include:

• Squinting constantly
• Using one eye at a time so the other can "rest"
• Tearing up frequently for seemingly no reason
• Eye rubbing 
• Excessive blinking

These signs of eye strain can also be the result of an isolated incident such as staying up all night playing video games, so rule out these types of lifestyle eyestrain before assuming that your child is nearsighted.

If you observe several of these signs occurring in your child's life over a period of time, especially if they gradually worsen as time goes on, it may be that your child requires corrective lenses. Once you're sure the symptoms are chronic rather than caused by, say, a marathon TV-watching session, contact an optometrist, such as the Glasses store, for a recommendation. You may need to schedule an eye exam earlier than you were expecting to.