The project manager should validate if the training request is within the scope and budget of the project before approving or rejecting it. The training request may be a valid requirement that was not identified during the planning process, or it may be a nice-to-have that is not necessary for the project success. The project manager should evaluate the benefits and costs of the training request and compare them with the project baseline. If the training request is within the scope and budget, the project manager can approve it. If the training request is outside the scope and budget, the project manager should send it to the change control board (CCB) for approval. The CCB is responsible for reviewing and approving change requests that affect the project baseline. Rejecting the request without validation may result in missing a critical requirement or losing a valuable team member. Approving the request without validation may result in scope creep or budget overrun. References:

PMBOK® Guide, 6th Edition, Chapter 4, Section 4.5.6, “Change Requests”

PMBOK® Guide, 6th Edition, Chapter 5, Section 5.6.3.1, “Requirements Documentation Updates”

PMBOK® Guide, 6th Edition, Chapter 7, Section 7.4.3.1, “Cost Forecasts”

PMBOK® Guide, 6th Edition, Chapter 9, Section 9.3.3.1, “Resource Requirements Updates”