I will 2nd what Garret said, earlier.... long tones are great for enhancing lip strength. ALSO: Do lip slurs in all 7 valve combinations. Start at low C, with all three valves open, slur up one interval at a time (no tounging - it`s all lip movement.) After coming back down, then do slurs with the low B combination (middle valve.) Do these slurs as high up as you can, and be sure to drop your jaw to sound out those low notes. If you make it a fight to reach as high of notes as possible, and do it everyday, your range and strength will increase.

And yes, it is true that shallow mouthpieces help a great deal in the upper register. The only thing I don`t care for with my Yamaha 14a4a is the fact that low notes are so "airy." This could be simply that I need more practice to clean `em up, or just need a new mouthpiece. I will be purchasing a Monette STC-1 B2 pretty soon. I`m convinced that Monette mouthpieces are supreme, even though I`ve never played on one before.... lol.

Roll bottom lip in and kinda say an "eee" syllabyl as you play.

curl your bottom lip up

hey you just need to go up your scales and keep on going for make sure your air is fast and that you have good space between you teeth ok have fun and you well do better next just think in a 2 two year you might be in marching band if you don`t give up on play the trumpet beleive i didn`t but with some help i got 1st chair and its my frist year so just keep at it and you well do fine pluse alot of the 7 grade dont get the high notes it takes time and lots of practices so don`t lose hope love always jessica

ta from low c - A, tee from b up, n too for low c n below... basically dats like the sorta sound u make wen u go play... my teacher juz taught me dat... im nooby

Theres an exercise my teacher taught me....

If you hold your horn by the valve caps (left hand) only (and don`t put your right hand in the finger thingy), and then practice some tunes like that, you`ll learn to not use too much pressure. If you can use your diaphragm more to get the range and notes, then you wont have to use your lips as much. Then, when you do play normally, if you do press on your lips (which i am NOT advocating, its really bad practice) you will get even higher notes.

Mainly, just have patience. Its all about building up your diaphragm and lips.

Also, what is a double C? 2 octaves above middle C? or 3?

I can play my high G,A,&B but i just cant get my high C. Can it be my age, Because im only 12, or is my technique. Please Help!!1

Oh yea its mostlikely somewhere in your form or technique. Usually (not saying that you are or anything this is just an observation) if a beginning musician doesnt have a good private teacher or the drive to learn things quickly and efficiently, they will develop there own restrictions or another words bad habits.
Some of the these could be incorrect application of the air, incorrect formation of the embouchure (i.e wierd puffing that either lets air escape or bad response to notes [i had this]), and of course bad application of pressure w/ bad horn angles.
These are some examples of "bad habits", or better said you can count on them being "pedagogically" incorrect. If you have the drive to get better and trust yourself to learn fast, find a private teacher and have him/her give you an analysis. Remember if you dont have the mindset to be serious, i would give it a couple years untill you "mature" a little more. Im not trying to put anyone down but its just much more cost and time effective to wait for your time to excel. If you think your not ready for lessons you should pick up as many ensembles as you can, like marching band, jazz band, etc. Nothing beats those expieriences as a young musician and i wish that i could go back and do it over. At my university we are having a jazz festival and to see all of there faces, its priceless. In fact, it gave me a better performance when my jazz band was able to perform.
So if you think you want to take things to the next level, decide to get lessons and expierience in many styles of music.

ummmm... i`m in 8th grade and high noted are no problem and i even have braces.
advice
1) use light pressure on your lips
2) dont squeze with your lips use your diaphram do push the notes out(that will only work if you are sitting up strait)
3)if all the rest fails look for a new mouthpeice. different size probably like a 5c from Bach a recamend

good luck

Hey to the wanna bees, and hey to the ones with the mojo ! Gotta tell ya, the band director is right about the pressure. At 16 we were doing maynard songs in the jazz band and I cheated using a jet-tone. I could do one song and to not play the next day ! I`m 43 now and bought my ax off e-bay for 98 bucks. That was 2 months ago. The day it arrived my pecker got hard.......I was going to scream again......NOT!!!!!. I ordered jet-tone mouth pieces, and my old schilke 13a4a. The 13a4a came soon and I started to play the scales but I have thin lips, and it was too big(so I thought). I remembered then about a pencil theory that I heard, and started with that training. I now drive truck during the day , so a pencil sticking out of my mouth is no big deal..Then I heard no more than 3 minutes a day with it. So.....I tore into a bic pen and use that for 3 min. at a time about 20 times a day. I use the small end, and blow through it. It biult the muscles in the neck and under the chin. After 2 weeks of this my range was within 3 notes of my range when I was hot !( that was with the 7c mouthpiece that came with the horn.) My jet-tones arrived, and yes they are very comfortable, but the sound sucks and I tire easily( I push to hard....old habit). My schilke 13a4a gets the job done for me without effort.Sooooo.........For you newbees.
#1.Get the book !
#2.Use the pencil(or pen).3 minutes of this is like an hour of play time.......make it burn baby!!!!!
#3.Scales..........Scales........Scales........
#4.Set your amishire for a "G" above the staff, and do the "C" scale 2 octives..repeatedly !
#5 keep your jaw forward and your tongue arched.

Simply keep your lips tight and increase the rate you blow into your mouthpiece. I`m a begining trumpet player, as well as an advaanced strings player, and this works well for me.

bigger mouthpiece = not so good tone

Sorry ryan but you are semi wrong(or correct, however you want it). A bigger mouthpiece doesnt always give bad tone, it only makes a bigger challenge to produce the same sound as a smaller mouthpiece would. The bigger the mouthpiece you play on especially for the upper register will help build muscle for endurance and range. I worked my butt off and learned how to play a g above high c on a Bach 1 1/2C. I have more endurance than anyone i know and can always play paint removing f`s. I then worked my up to smaller mouthpieces. I am on a 3c`ish MPC now and working on my a b and c above high c. I also have the shewlead from yamaha, very good lead piece.

Dark-I have three words for you and those 3 words helped me get the high notes:

TITEN DA LIPS!!!!

huh, i was having some trouble, one thing i did unintentionally was take a 2 day brake and my range has gone up a full 2 notes or so since i last played, take a couple brakes time to time, they help! Thanks you play practice for not giving me time to play! lol