For early finishers or students that rush (rather than allowing them to proceed to a "free subject painting" or choice time) encourage them to reflect further on their work:

"How do you think this image might have more impact if you used a different color scheme? Could you save your work now and see if you can come up with a scheme that shows us (how dark and creepy this night is, how happy this girl is, etc.)?"

"Which tools can you use to further manipulate this image that you haven't tried out yet?"

"Just to make sure you're absolutely finished with this piece, save your work now, and try out an alternative solution. You can always hand in the previous version if you don't like the new solution."

"Have you explored this layout using other fonts instead? Save your work now and show how a different font can entirely transform the same message."

"How can a font style reinforce a strong message? Is it possible for a font to detract from a message? Do you think this font reinforces or detracts from your message? Why?"

During paint and drawing tool demonstrations, rather than reciting tool functions, use Demonstration Dialogue:

"What do you think this tool is going to do?" (solicit predictions and educated guesses)

"Is this a painting tool or a manipulation tool?" (paintbrush vs. skew or filter)

When a student wants to skip ahead and is trying out difficult tools or running into trouble, thereby spreading your instructional time thin:

"I see you have discovered the (insert impossible tool here), which I haven't demonstrated for the class yet. Stick to the tools we have learned together for this assignment. We can meet at lunch and try out the advanced tools later if you like, then you can teach it to others."

There are no "wrong answers" in art, but in design some solutions can be more developed than others.

Instead of: "These colors aren't realistic enough."
Try: "Have you used any photographic or Primary Source references to help you choose your color scheme yet?"

Instead of: "That font isn't appropriate."
Try: "What does the Old English font signify in your space station collage?"

Instead of: "I can't read this type style. Change it."
Try: "Consult with three other students to help you decide if that is a legible color combination."

Could you tell me what this picture is about?
Solicit storytelling and tease out details that are missing. Avoid telling the student what they have painted, especially if it is yet unclear.

What kind of mood are you aiming for? How do the colors support that?
Encourage them to choose colors thoughtfully and explore alternatives.

How did you create this area?
Point out the most difficult and masterful thing they have done and invite them to explain the procedure to their peers (recall technique).

What do you think is the most impressive thing about this painting?
Encourage them to identify successes and show pride in their work.

What do you wish you could do to this painting to make it even better?
Solicit technical help from peers.

If you were to crop out your favorite part of the picture, which part would it be?
Encourage them to look at the same painting in a new way, then use the cropping tools to explore issues of composition

Have you explored any alternative color or composition solutions to this painting yet?
Encourage multiple (seriated) solutions using the same "base drawing", saving the image as it develops along different paths.