First, if this is a public school they are likely entitled to governmental immunity, which means that the governmental entity like a public school is protected from lawsuits unless a statutory exception applies. In this scenario, the only two exceptions would be the highway exception which provides that the governmental entity is responsible for maintaining highways or the public building exception. Unfortunately, I do not think the the parking lot of a public school would fit into either category.
With that said, please be aware that if you should pursue a claim against a governmental entity, you must submit a notice of claim to the governmental entity within 120 days from the date of the accident. These notices must be very specific and contain certain information to be in compliance with the statute. In other words, I would suggest having an attorney review your case as it does sound like you had a nasty injury. Be that as it may, governmental immunity is a powerful beast and not easily overcome.
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