More money spent does not necessarily mean better education.
The main reason for the difference in expenditure is the high pay required for highly skilled and educated workers in the U.S. and other high income countries. This is also what really underlies the high cost of health care.
This is a problem but, as problems go, this is a good problem to have to deal with.
Some ways to ameliorate the problem. Regarding the demand for highly-skilled and educated workers, we can:
(1) fight over-credentializing. Do primary school teachers need graduate degrees? Do lower-level professionals such as an assistant manager of a department store need a college degree? Do plumbers need a prep school education at H.S. or would a vocational education be more appropriate? Do people need Medical Doctors for their primary-care, or would Physician Assistants and Nurse Practitioners be sufficient?
(2) encourage home-schooling and self-education, and healthy living, and stop subsidizing schooling and health care so much.
(3) introduce choice and competition to the provision of social services.
Regarding the supply of highly-skilled and educated people, we can:
(1) restore the two-parent family, our children and our boys especially are being lost in shuffle.
(2) raise the standards, expectations and discipline of schooling.
(3) bring people who love math into the classroom. One of the primary purposes of landing a man on the moon was to encourage young people to pursue math and science.