From your child's first scribbles to her carefully written school book reports, she goes through a series of developmental stages that help shape her handwriting. It takes time to remember which direction each letter and number is supposed to face, and it's common for children to write them backward from time to time.
It's normal for children in preschool and the early grades to write their numbers backward. Children at this age are just learning to form their numbers correctly. Your child is still developing the hand-eye coordination necessary to copy and write things properly. Also, if your child is very young, she may not understand that numbers always look the same and relate to a concrete concept; she might instead see writing numbers the same way she sees drawing trees, for example: to her, they look similar, but it's not important which way the number 3 faces.
Reading and Writing
As your child learns to read and do simple math problems, she'll begin to understand that numbers and letters can be put in a certain order and that they mean something. As this concept sinks in, she'll begin to understand that numbers are meant to be formed a certain way and will start to pay attention to how she forms them when she writes.
When to Be Concerned
If your child is doing well in other areas such as reading and math, she probably just needs a little more time to get the hang of writing her numbers. Usually kids can write all of their numbers correctly by the end of second grade. If your child is still writing backward after that, talk to her teacher about it and any other problems she might be having.
Writing numbers backward may be a symptom of a learning disability such as dyslexia or dysgraphia, but writing things backwards is rarely the only symptom of these things. Watch for struggles in school, especially with reading and writing; trouble learning concepts like up and down, left and right, and over and under; difficulty following two- or three-step directions; and trouble staying organized or focused. If you have a family history of learning disabilities, your child may have a higher risk of developing one.
How to Help
If you're concerned about your child writing her numbers backwards and think it may be part of a bigger problem, talk to her teacher and pediatrician about getting a referral to a developmental expert who can test your child for learning disabilities. At home, have her practice writing things for fun, such as signs for her bedroom door, stories about her favorite TV or music stars, or menus for each night's dinner. Correct her gently; remember she isn't being bad by not writing her numbers properly. Don't punish her for making an error. Be positive and encouraging, and chances are she'll be writing just fine before you know it.