Ambrose et al. suggests that there are three key points which make feedback more effective: 1) focus students on key knowledge and skills you want them to learn; 2) provide feedback at a time and frequency when students will be most likely to use it, and 3) link feedback to additional practice opportunities for students.

They also suggest the following strategies to address the need for targeted feedback:

• Look for patterns of errors in student work to discuss with the group
• Prioritise your feedback according to the most prominent learning objectives
• Balance the strengths and weaknesses in your feedback
• Design frequent opportunities to give feedback
• Provide feedback at group level
• Provide real-time feedback at the group level (e.g. commenting on group discussions)
• Incorporate peer feedback
• Require students to specify how they used feedback in subsequent work

Source: How Learning Works: 7 research-based principles for smart teaching, Ambrose, SA, Bridges, MW, Lovett, MC, DiPietro, M, Norman, MK, 2010