I'm in education, too (not school, though) - big organisation - and HR are a bunch of chancers, here.
They don't provide or organise any training - its all done by specialists in different academic or support departments.
They dont draft or update many of the policies - again, managers in other areas of the organisation do most of that
They dont provide support to employees - never heard of an employee confiding anything in HR.
They are like little shittting-it lapdogs to senior management. We have been through two restructures in recent years, and at the consultations with staff, they always seem ill informed and really flustered, and just nod at everything the managers say.
They arent actively horrible people, but they're not helpful. They take an age to get back to you and can never seem to provide any information you might need.
I've been with my organisation for three years, and the only real contact I have had with them has been when I was underpaid for 8 months and they had to sort it out...and they still managed to make it feel like it was my fault 
Maybe there are really forward thinking, hard working HR depts elsewhere? I am willing to be convinced...