First of all, please don't barf so many details about your case on public websites, where anyone in the world can read them.
When you go to court on Monday, you should ask the judge to appoint an attorney from the Public Defender's office... then let your lawyer do the talking. Your lawyer will have all the facts of the case and can talk to the District Attorney handling the matter... which means your lawyer can do a lot more to help you than a stranger on the Internet who doesn't have that kind of access.
The "civil demand" issue is completely separate from the criminal case, and you can probably just ignore them. There are a handful of law firms that work on a commission basis for stores; if the law firm collects, they keep a percentage of the money and send the balance to the store.
Expenses, like printing and postage, come out of the law firm's share... so they usually give up after a couple of letters go unanswered. I have never heard of a single lawsuit filed in California because somebody refused to pay these outrageous civil demands... and even if they did sue you, they couldn't justify charging you more than $500 under these circumstances.
See my legal guide, below, for more information on civil demands.
Ok, first thing is calm down. You may have been arrest for a felonies but it could be charged as misdemeanors. You need a skilled criminal defense attorney who knows the courts and the prosecutors and what they are willing to do in the way of pleas. If you (or your parents) can’t afford a private attorney the court will appoint a licensed attorney call the public defender. The PD will help you. Get your grade cards and resume together and give a copy to your attorney. You need to be packaged as the good kid who did something foolish, once. The pliers are going to be an issue, it shows planning. These cases are really hard to predict. It really depends on what the DA, or city prosecutor wants to do.
Hopefully, the prosecutor will allow some form of informal diversion. You may have to do a bunch of community service/labor in exchange for a dismissal. Most importantly your attorney will have to work to have this not be a felony conviction. Felony convictions dramatically alter your civil rights and future potential. With misdemeanors you will still have issues if there are convictions for theft related charges. If you use the services of the PD listen very carefully to what they say. Don’t BS with them or they mentally may move on to the next case. A good PD can do wonders on a case. They work with the calendar DA day in and day out.
If your parents have the resources then hire the best skilled, experience, and knowledgeable criminal defense attorney who practices in the court where you case is set. A private attorney can spend the time packaging and positioning the case. But, make sure that attorney know the court and the prosecutor.
First thing though is calm down and relax. Keep your expectations about this realistic. This will be in your life in some form. There will be an arrest. Most likely the charges will get expunged, which in California is a very weak form of relief. But, you will survive and move on beyond this.
When you do hire a lawyer or accept a public defender, make sure that he or she doesn't accuse you of "barfing" when you talk about your case. Such an individual is an insensitive prick who will not do much to help you. And you will need help based on the facts you have imprudently published here.
One wonders why if one is a "stranger on the Internet" one would keep posting on subjects he admittedly knows nothing about.