The pie chart above shows the breakdown of elementary and secondary students in the USA. Data is for 2013, from the National Center for Education Statistics (with homeschooling numbers extrapolated from 2012 data). Educational options are a hot political issue right now, with changes to education policy likely under the Trump administration. What those changes will be is unclear.
Of course, the US educational system does need some improvement. In the 2015 PISA global education survey, the US ranked equal 23th in reading, 25th in science, and only equal 39th in mathematics. Canada did much better (2nd, 7th, and 10th), and Singapore came 1st in all three categories.