Like many areas of learning, the best assessment of writing skills is to evaluate several examples of written work.  To create a representative sample of a student’s writing, I have them write (on different days) the following exercises (the topics don’t really matter):

• A descriptive paragraph, an opinion paragraph, and a how-to or instructional paragraph.
• A persuasive essay
• An informative or explanatory essay
• A narrative
• A fiction story
• An instructional essay
• A book report

Of course, younger students won’t need to go much beyond the first exercise, but I would definitely have them produce paragraphs on several different occasions.  Middle and high school students should be able to write all of the above.

To evaluate writing fairly and effectively, I use rubric-style grading.  This will give a valid framework within which to evaluate writing skills.  Here are some links to rubrics I find helpful:

Common Core Writing Rubrics Grade 5

Common Core Writing Rubrics, Grades 9-12

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