I've never been an IP but:

How about telling him to think about what he needs to work on, then he needs to plan his next flight to include those tasks.

Tell him on his next flight he will demonstrate those tasks and then self critique without your prompting or input. You are either teaching someone to command an aircraft or you are holding thier hands. If he is planning on being a commercial pilot you will be handicapping him by holding his hand.

He will either put the time and effort in to learn the standards or eventually realize that he is paying for his own lack of effort.