I can't help with your second question (sorry!). I do have ideas for the first one, because I experienced that too. I like to make up stories. I have this story that I came up with in preschool when I couldn't sleep during nap time, and I kind of come up with all sorts of branches off of it.

Or you could try listening to music or a podcast of some sort. I did that for a while, because it gives you something to think about while still resting. 

Ok, so I do have some advice about question number one! Sometimes when I'm trying to sleep my brain simply will not shut down. I've got about a million things I'd rather be planning or doing or thinking about. So I've started keeping a notebook by my bed and writing down any thoughts or ideas that I don't want to forget. I also make a to-do list for the next day, just to organize everything. I also have this thing I do before going to sleep where I make a list of everything I'm grateful for, all the nice things that happened today, all the things I need to work on. That helps me calm down and organize myself.

If my mind is really cluttered and random thoughts keep popping up I have to organize my mind itself. I picture my mind as a room with shelves, and picture myself sorting everything into it's own box. For example, if I get a song stuck in my head I can picture the song as peice of colored string, then smooth it out and shut it in the drawer where songs go. If I keep recalling something I don't like or want to keep on the surface of my brain, I place it in a certain box, then shut the box. Each thought has it's own place, and I know what every box and drawer looks like. It helps me focus myself and quiet my mind.

There's also a breathing technique my dad taught me: Breathe in through your nose for four seconds, hold for six, breathe out through your mouth for seven seconds. I have also recently descovered the goodness of chamomile tea! It actually calms me down when I'm feeling stressed, and I've started drinking it before bed. (Just make sure you time it so that you don't wake up in the middle of the night to go to the bathroom.)

As for high school... all I can say is keep an open mind. It's probably not going to be too different for you as you are continuing homeschool, so just try to have fun with the new expirience of taking a class at public school. Always ask questions if you don't understand something (ask the teacher, ask the other students... whoever you think will explain it better). Always divide up the work on group projects at the very beginning! You don't want to end up with one person doing everything and everybody else shirking off. It's not a lot of fun on either end of the spectrum. About group work: Find out what you're good at! Then try to pair up with someone whose abilities complement your own. 

And about turning fifteen, just remember that it's going to happen whether you feel prepared or not. You'll grow into it! Actually, I have never in my life felt prepared for turning a new age. It just sort of happens. And anyway, what changes? Just a number. You're still the same person, you're still learning and growing. Good luck and happy birthday! I hope some of this helps (and that I actually made a little bit of sense).  

Ohh, I can help with sleep I think! Maybe xD

So I cannot obviously diagnose anything, but it sounds like insomnia. There is Primary (not caused by other health issues) and Secondary (caused by depression, asthma, arthritis, heartburn, etc.). Then there's acute (short-term) and chronic (permanent/long lasting) insomnia. In general, acute insomnia is caused by things like stress (such as turning 15), environmental factors (noise, light, temperatures), emotional/physical discomfort, sickness, etc. Likewise, chronic insomnia is caused by depression/anxiety, chronic stress, or pain/discomfort at night. The symptoms of insomnia, in general, are sleepiness during the day, trouble falling asleep, waking up early or middle of the night, tired when waking, irritability, issues with concentration/memory, etc. (This is all from WebMD if you want to learn more).

Now that I gave you the medical facts... uhh... yeah, I do that a lot. Anywho, now let me explain some suggestions I recommend. Chamomile is AMAZING. Chamomile tea (some include vanilla for those who like taste), and a chamomile essential oil spray (the oil is kinda pricey though...) on your pillow are fantastic. You can also do a chamomile essential oil blend in a defuser or large bowl of boiling water and breathe in the mist. Also do lavender essential oil drops on your bed! Or a little packet of it you tuck under your pillow which are sometimes found in stores. Again, diffusers work too. Both chamomile and lavender work best, together or separate. 

Next, do some yoga and meditation! If you haven't done this often, you might feel a bit... silly? Like out of place. But no one will judge you, and if they do shame on them. Not only will yoga build strength, agility, and balance, it along with meditation clears and settles your mind.

Have a bit of water before bed, do NOT go online, and picture something opposing to your dark thoughts. Like when I was younger it was "cupcakes and rainbows" and now it tends to be me saving the world xD

Destress yourself. Let everything go and do not worry about high school and being 15. Are you homeschooled or public schooled? I can't remember, but either way, I know you will do fantastic. To help with sleep also, search up some good apps. One, it's called "Mindful Rest" or something. It plays certain range of sounds depending on your situation. Find a good recording one that will record any sounds you make at night. This way you can track how often you are subconsciously waking, talking, sleep walking, or snoring (yes that too xD). Then you at least know *why* you cannot sleep. If you cannot find a good sound one that I first mentioned, turning on classical music or nature music (rainfall, rainforest, ocean, etc.) will help rest your mind. I hope this all helps!

I have to go do a nature study so I won't be back for a couple of hours. But when I do return, I'll give you advice on high school/turning 15! Best of luck, Silver! 

I have a few tips for the sleep thing that might just help you! I had trouble sleeping for awhile, still do some nights. I find that some nights, it just takes me longer no matter what. But I have some relaxing stretches you might want to try that really make your body relax and helps you to feel tired. Tense up your feet, count to ten, and relax them. Do the same with your calves, thighs, glutes, abs, back, neck, all the way up to your face muscles, and then tense your whole body. It really relaxes me when I do it!

I used to listen to audiobooks A LOT because it sometimes helps to have something to listen to and think about so your thoughts don't just kinda wander, making it hard to fall asleep.

Another thing. I take two pills that help me fall asleep. The first one, melatonin. Melatonin is a natural chemical that your body makes to help you sleep. They make melatonin pills that you can take to make you more drowsy. I can give you the brand name I use and you can talk to your parents about it if you're interested. The other one is called Calms Forte and it is just a natural calming aid, which helps me relax at night. It also helps you relax and calm down in the daytime. 

I hope this helps! 

Thank you everyone so very much for this! I really appreciate the helpful tips and hope to put them to good use!! Your encouragement is so helpful! Thank you!! <3

I don't know if this would help, but I like doing some stretches before I go to bed, just to relax. Like yoga but not all of the sixth sense/inner eye stuff.

I'm a homeschooler going into highschool too, and so far it's not that different than middle school. Not saying that homeschoolers are smarter than public schoolers or anything, but sometimes homeschooling gives you the flexibility to really learn things at your own pace. I think you might actually be surprised by how much you do know.  

As for turning fifteen, it's just a number. You might not feel like a fifteen-year-old, but that's just a preconceived standard-- be yourself and you'll end up growing into your age.