And Now, A Statement from the Confused Teacher
It's easier to simply check problems correct or incorrect on a test. Then this works out into a percentage grade. That grade can then be converted into a letter grade. As a teacher, why waste my time on writing comments and giving suggestions? That takes much more time and is less efficient. What a waste of time. I'll teach them, then I will grade them. Then, bam, I'll teach them again. The perfect system-Efficient.
Efficient or Not Efficient, That is the Question
The above would be true, unless you look at the definition of efficient. Then you've got yourself a problem.
Efficient: 1) achieving maximum productivity with minimum wasted effort or expense 2) working in a well-organized and competent way.
Feedback is shown to have a great impact on learning. Nothing has a greater impact than good feedback.
Minimum Wasted Effort-
Use in-class formative assessments and provide immediate feedback regularly.
Well Organized-Have systems in place to organize feedback. Formative assessment such as quick checks for understanding using a randomized way to collect answers from students. This could be as simple as using popsicle sticks to choose who will answer next. You could also use a clicker system but technology, in this case, does not necessarily make it better. Maybe you have a system at the end of class for student to put sticky notes on the door as they leave the room.
A great teacher understands the research. The research tells us feedback correlates in a very strong way to learning.