Adjusted for inflation, the average annual spending per public school K-12 student has risen from $753 in 1920 to $18,614 in 2021, or by 25 times. These figures don’t include state government spending on administration, the unfunded liabilities of pensions for government employees, and the costs of post-employment non-pension benefits (like health insurance). The second link below contains the arithmetic and algebra questions from the 1885 high school entrance exam in Jersey City, NJ. At the time, the school district was spending an average of $13.24 per student per year. Adjusted for inflation into 2023 dollars, this is an average of $449, or 1/41 the national average spending per student in 2021.