Key Concept of Earned Value

Earned Value is a means for integrating Costs and Schedule. Earned Value refers to the determination of how much work has been performed on the basis of what was budgeted for the work that has actually been completed. The idea is that an owner has earned whatever amount was budgeted for the work that has in fact been completed. This value then becomes a measure against which other cost and schedule data can be compared in order to determine actual coast ans schedule status.
The earned value concept compares several measures to obtain an overall picture project status: BCWS, BCWP and ACWP. Comparing the BCWS and the ACWP values to the BCWP gives us an indication of variances from hte expected schedule variance and the cost variance.
If you are interested to get to the point to understand the concept of Varned Value and use it practically in your organization, then you can click this hyperlink to see the course modules. The proper tools is using P3 or P6 as suggested by Kent, the course facilitator.