Modern planning begins with the concept of the Gantt chart.
Gantt Chart
The concept of the planning tool was developed by Henry Gantt as a tool for engineering an entire project process by sequential tasks. It was developed to improve industrial management in the early part of the 20th Century, at the very time that our educational system was being designed.
The concept of Gantt charts shared the same principles of Scientific Management 
as the original architects of our traditional education system.