All of the three words could be verb and noun.
To arrange resources (time, human etc.)for a specific work,event or a period of time.
This is the scheduel of the Spring Festival holiday.
The boss let Wang to contact client.
A relatively compelete and considered plan that include the goal, method, shedule etc. As a verb it is more formal and used in written Chinese.
This is the study plan of next term.
The government plans to build a hospital.
打算 intend to do/intention
It is more casual and informal. For someone intend to do something or just think about to do something.
I want to go to a book store tomorrow.
She does not have the intention of working.