This is such a simple idea I can’t believe I didn’t think of it before!
When doing an extended activity that lasts 20 minutes or more, stop the class halfway through the activity. Have them put down their pencils/pens etc, stand up and quietly circulate around the class. They can look at the work of their classmates and gather ideas of what they might like to do in their own work. They then return to their seats and continue the task that they were working on, but can now integrate lots of new ideas and techniques that they’ve seen.
This works brilliantly both for group projects like a science investigation and also individual tasks in art. I’ve found this really raises the bar of what the students can accomplish, and also allows individuals or groups that were struggling to get a fresh batch of ideas to work with. Also, if children know that the rest of the class will have the opportunity to view their work, they are often motivated to work even harder as they know they will have an appreciative audience!
As ever, make sure you set ground rules for behaviour before attempting this activity. You want to establish that students are supportive of each other and comment on the features they like in other people’s work rather than laughing at or denigrating the work of others.
Obviously this activity works best when the whole class are attempting the same tasks.
You could extend this activity and have students leave written comments for other pupils to read when they return to their seats, or repeat this activity at the end of the lesson so that students can see how work they saw earlier has progressed.