I have an 7 year old will be 8 soon and she will not go to sleep. I put her to bed and she says she is not tired and is constantly getting up and will lay awake for hours. When she finally does sleep its only for a few hours. This has been going on for the past 2 weeks.
There could be many reasons. Some of the main issues to look for include: does she use a TV/computer/cellphone/tablet prior to going to bed. These all interfere with the brain's sleep mechanism. Is there an LED, especially blue colored, night light in her room? That can also interfere with the sleep mechanism.
You might also want to check her diet to be sure she isn't eating anything that will induce hyperactivity within 2 hours prior to sleep time: no sweets, no oily foods, no starchy foods. Check her pee, if it's very yellow, start giving her more water during the 2 hours before sleep to ensure her pee is more clear than yellow. Additionally, be sure she has a consistent sleep time and a sleep ritual built into her schedule. A good sleep ritual includes going to the toilet, taking a bath, and reading with Mommy or Daddy prior to lights out.
Please note that bed time would change a bit as a child grows older. Assuming that you are putting her to sleep at the hours an 8 yr old would typically sleep, Here's a sample checklist that I would use to see what has changed in 2 weeks
a) Did she stop doing a particular activity recently? (Eg., swimming as it's cold outside). Some kids have difficulty sleeping when they have no physical activity in the day so if that's the case, you may have to keep them busy with something to do.
b) Did something very exciting happen at home or school ? Some kids get too excited about an upcoming vacation or a school event that they keep thinking about it without allowing their minds to rest. This is a temporary phase and things would soon be back to normal.
c) Did she recently change her food pattern ? If yes, you have to make sure to stick to a diet similar to what she's used to and identify the food which is keeping her awake.
d) Has she been watching an additional show on TV or playing some new game ? Stop any digital activity an hour before bed time. Only books (physical) should be allowed.
At almost 8 she probably knows whether she is tired or not. So if she states that she isn't, then either she really isn't tired or she has some reason for trying to avoid sleeping.
If she doesn't fall asleep all the time, then maybe her need for sleep really has gone down a bit. You could try to let her stay up for an hour more in the evening and see what happens. Going to bed when you're not tired just makes things worse. Humans, children included, have individual sleep patterns, and sometimes one might have a period where less sleep is needed. And that's fine.
If she does seem too tired and falls asleep during the day, then something else is going on. Try asking her why she doesn't want to sleep. She could be scared of something or she could be acting out. She might be having nightmares or other problems that makes sleeping at night bad or scary. If she's acting out, try to find out why she is mad at you and solve that. Not sleeping might be her way to control a situation she feels she has no control over.
Either way, don't fuss to much about specific bedtimes. It's okay to take it easy and coach her into sleeping instead of sticking to a strict schedule. There are a lot of things that helps to make one sleepy, such as temperature changes (go outside for a walk and come back in or take a warm bath), repetitive tasks (folding clothes etc.) or reading.
Try talking to her. The important bit is not how many hours she sleeps, but rather that you are sure she isn't distraught about something and that she isn't sleep deprived. Her mental health and well-being is more important than a bedtime.