Thank you for your question. To answer:
Your question requires two answers - First, it is not a violation of Texas criminal law to keep a handgun or other firearm in your locked motor vehicle on a school parking lot. Therefore, you will not be arrested for such activity.
However, Texas law allows schools to regulate and prohibit their employees from keeping a firearm in their locked motor vehicle in a school parking lot. This could subject you to disciplinary action from the school, including termination, but you would not be arrested.
