A bit of background:
Last week, my car wasn't starting due to the dead battery in my remote key (I only have one key), and I knew this from a CEL code that I was able to look up on this forum (P0335).
When I push down the brake pedal and push the start button, the car turns on, but the engine doesn't start. I just hear a "click" as the car fails to start. This was fixed by replacing the battery in my key and also charging the car battery. The car then worked normally up until yesterday.
As I was leaving school, I tried to start the car and the same thing happened, a click when I tried to start the car and the engine doesn't start. However this time I know it's not the key. I assumed it was the battery so I tried 3 different sets of jumper cables with 3 different cars, and no luck. I had to leave the car there overnight and take the battery home to charge it overnight, and this morning I put the battery back in the ISF and it still wouldn't start. My friend's boss has some mechanical knowledge and said it could be the starter.

I just want an opinion from this forum; as I'm writing this, my car is parked at the university library.

 

Id get the battery load tested first, it could have full charge but still be bad

 

If your car battery is dead, and you're constantly having to recharge it, I'm going to say that's the main culprit right there... get your battery tested and that'll determine your next steps.

 

Def get the battery tested, sounds like a bad cell

Are you hearing cranking?

 

Like everyone else said take the battery to a store such as Autozone, oreillys, napa, interstate, walmart and have them test the battery first.

if the battery checks out or you get a new one and it still won't start you might be looking at replacing the starter. You might also check fuses. If you don't have a place to work on the car or don't have good mechanical skills, you probably need to find a good shop that can properly diagnose and repair the issue at this point.

You will want to be pretty certain that the starter is the issue before you replace it as it is no small task replacing. The car will need to be put up on jack stands/lift and the engine and trans need to be supported so the subframe can be lowered to remove the header for access to the starter.

 

Could be a bad cell in the battery, but if it's not starting with a jump, it's sounding more like the starter solenoid. Most people replace the whole starter, but as indicated above, it's no small task depending on your skillset.