Ask your students how much homework they have time for, especially if they are adults. People with full-time jobs and family commitments are unlikely to be able to do more than a couple hours of homework for a language class each week, although some might want homework every day. If your students are children or teenagers and you know they will ask for no homework, aim to set homework about once or twice a week, except when they have other exams.
Set short written assignments relating to what you have done in class. Be very specific, particularly with beginners. "Write an email to a friend describing what you did on Sunday" is better than "Write about your childhood."
Collect the assignments and go through them later. Circle a few of the major errors in each one, but do not make any corrections at this point. If several students were making the same mistakes, make a note. You can address these problems in a later lesson.
Hand the assignments back to the students and ask them to correct the circled mistakes, individually or in small groups.
Collect the assignments again, and take them home for corrections and comments.
Prepare for the activity by writing the first sentences of short stories on several sheets of A4 paper. Try to make them varied, for example, with lines that suggest a horror story, a thriller, a comedy and a science fiction story.
Divide the class into groups of three or four students. Give each group one sheet of paper and ask them to continue the story.
After about 5 minutes, ask groups to pass their sheet of paper to the next group. Ask groups to correct any mistakes they see before continuing.
Help by moving around the groups as they work and offering suggestions.
Repeat until you have spent the time you allocated for the activity, and ask groups to finish the stories they currently have.