Stack of papers ready for grading with pen and glasses

The Annual Global Cost of Grading Student Work exceeds $60 billion.

I reviewed reports from UNESCO, OECD, the Gates Foundation, National Science Foundation and other sources to learn the following statistics.

Global Context

  • There are 28 million teachers and there is a need for 11 million more to fill significant gaps.
  • There are over 11 million graduate students and the majority of these people work as teaching assistants supporting undergraduate instruction.
  • There are over 570 million children enrolled in school. The school age population is larger, closer to 2 billion (655 million in primary, 781 million secondary, 608 million in post-secondary).
  • The student-teacher ratio is around 25 in primary and 18 in secondary.


  • Teachers report that they spend, on average, 2 to 3 hours per week grading student work. Over the 36 week academic year, this amounts to an estimate that each teacher spends 100 or so hours per year grading student work.
  • Graduate student teaching assistants spend 80 to 100 hours per semester grading student work.


  • In 2009–2010, the average salary of teachers in the USA was $54,000 which exceeds $20 per hour.
  • Graduate student teaching assistants are paid $20 per hour or more.

The Lower Bound

On average, each of the 28 million teachers and the majority of the 11 million graduate student teaching assistants spend 100 hours per year evaluating student work. The salary expense of, say, 30 million people each grading student work for 100 hours per year with each hour valued at $20 is $60 billion per year.

Skilled human beings are spending at least 3 billion person hours per year evaluating student work. By eliminating inefficiencies, boosting collaboration, and improving the evaluation workflow, Crowdmark helps educators grade better.

Photo courtesy of Carlos de la Orden.

I thank George Craigen for pointing out an error in an earlier version of this post. —J. Colliander