It's not about what book you're in...it's about how you play.

A good violinist can make the simplest piece, such as Twinkle, sound like a beautiful and amazing piece by producing a gorgeous sound that the audience will never forget!  It's not so important what you play, it's how you play it!  

I remember in my middle school orchestra my stand partner was excited about a new, long, and advanced piece she learned.  When she played the piece for me, it didn't do her any justice as far as showing off her violin skills and it put her in a dim light. If it was the first time I heard her play, I would have thought she was a very average player (and that was not the case about her-she simply chose to learn a song that she wasn't ready for.)  Her sound wasn't how it usually is and it just seemed messy with many rhythmic errors.  Afterwards, she played a simple, two page piece we were learning in our orchestra, and to this day I remember how gorgeous she made it sound. What's the moral of the story? Go for quality, not quantity.  

Think of it this way:  If you listen to an instrument recording, would you rather hear a mediocre sounding, advanced level piece, or a level one piece that sounds absolutely beautiful? 

 This situation reminds me of an X Factor episode.  One (very talented) performer went over the top with their dancing, stage effects, costume, high notes, etc.  The other performer wore a simple dress and it was only her singing while playing a guitar.  Simon Cowell said although they were close to equal as far as singing ability, the second performer was much more pleasant to listen to because she stayed within her range and focused on what was most important: the sound of her voice!

When you are performing a piece, do any of the audience members know what level it is or what book you're in? Other than your teacher and possibly your parents, of course not.  

Practice and experience are the best ways to eventually have both, and if you work hard, you'll be able to play beautifully at an advanced level!  But until then, relax.  Of course once in awhile you should do a challenge piece and there should be deadlines and goals for level advancements, but it should be done at the right pace.  After all, what's the main point of playing an instrument? To produce a beautiful sound!  

~Regina