Here is an urgent special meeting agenda, also called an emergency meeting notice, with my comments below:

My comments:
This is indeed a rare example of an emergency meeting notice. School districts are required to post their meeting notices for 72 hours, and it appears this one was posted about 9 hours shy of that given that the meeting is at 8:00 am on Friday and the 72 hours would have run at 5:00 pm. Emergency meetings are governed by the Open Meetings Act at Gov't Code 551.045. When you get into the weeds, you will find: (b) An emergency or an urgent public necessity exists only if immediate action is required of a governmental body because of: (1) an imminent threat to public health and safety, including a threat described by Subdivision (2) if imminent; or (2) a reasonably unforeseeable situation, including: (A) fire, flood, earthquake, hurricane, tornado, or wind, rain, or snow storm; (B) power failure, transportation failure, or interruption of communication facilities; (C) epidemic; or (D) riot, civil disturbance, enemy attack, or other actual or threatened act of lawlessness or violence. And, then, there's this: (c) The governmental body shall clearly identify the emergency or urgent public necessity in the notice or supplemental notice under this section. The way I interpret all this, to boil it down, is to hold an emergency meeting the sky must be falling and...you have to say the sky is falling in your notice. On its face, I'm not sure this agenda does that. Why does 9 hours matter? Well, in the big picture it probably doesn't. But, it still has to be an emergency, a true emergency, and one thing is for certain - the unavailability of board members or missed deadlines, for example, shouldn't be the basis of emergencies. And, of course, if a school gets to cry wolf all the time, then when a serious public emergency is happening no one will take the notice seriously.
As to "Discuss/Approve budget amendment as presented", again, I think this is insufficient notice. What is this amendment about? And, if this is indeed an emergency, I think that being specific about the amendment is all the more compelling. True emergencies cost money, and an emergency budget amendment ought to be spelled out so taxpayers know how their money is being diverted.
I may update these comments up until meeting time...