Teachers should give primary children (aged 5~10) assignments for less than 30 minutes because they have enough instructions in regular school classes.

Teachers should give primary children (aged 5~10) assignments for less than 30 minutes because they have enough instructions in regular school classes.

I don’t think it is necessary for teachers to give primary children assignments less than 30 minutes.
First, there are some assignments that can not be completed in such short period of time. Although the children are not capable of managing with extremely complex event, there still exist some assignments that would take them some time to finish. Some group projects need to be done for at least a few hours. Let’s say, a group of children are assigned to paint a poster on paper. At first, they usually have a discussion about the designation of the poster, and then divide the different parts of work to each of the group member. After finishing the draft, they need to fill color in the blank to finish the final step. Even though their teacher has showed the instructions on class, those children still need to go through a series of process to complete the assignment. Even a group of adults cannot quickly finish the assignment in less than 30 minutes, let alone a group of kids.
Second, if the children are asked to complete the assignment in too little time, he has no time to revise it to make it perfect. For example, as a perfectionist, my sister wants her assignment to be brilliant. To reach her goal, she often checks her assignment thoroughly almost two times after she has finished it, to ascertain that no mistake exists in her assignment. Moreover, sometimes when she cannot find flaw in her assignment by herself, she would definitely ask me to view her assignment and offer her some advice. It is because her pursuit of excellence that makes her to be praised by teacher for every assignment and also, she can improve herself by discovering her faults and modifying them during each project. Had she been forced to finish her assignment in less than 30 minutes, she would undoubtedly not hand on so perfect assignment each time.