When I first moved to Texas I thought it would be a similar type structure. I assumed each school district would set an annual budget. Property valuations would be used to determine your payment or percent of that total budget. So if you had a $100K valued house and it increased 10% to 110K, but the overall value of property in your school district increased by 15% on average, then you would pay LESS in taxes because your portion of the total school district property values went down and it would be applied to a fixed annual budget amount.
The idea that property values would be done annually and if values went up the school district got more money without regard to budgeting and planning made no sense.
Of course with Robin Hood it really means that if property values go up everyone pays more to get approximately the same school district budget but the school district pays more to the State who then gives it to other school districts. Or the State lowers the per student amount they give everyone which would be paid from other revenue sources and they use the additional tax/Robin Hood funds to cover the state paying less of the per student bill.
Great system. Clear as mud.