Accurate (i + 1) Assessment for English learners

I have a total of four English learners in my class and they are all CELDT 4s, ergo, my CT and I teach at the "advanced" level for ELD Standards.

ELD Standard:
Write persuasive and expository compositions that include a clear thesis, describe organized points of support and address counter arguments. 

Assessment-Diagnostic/Entry Level: Academic (T.A.X.E.S.) Paragraph  

After completing the graphic organizer and the group discussion the students are asked to write an academic paragraph and are told to follow the T.A.X.E.S. model, which is tagging statement, assertion (Thesis), example, explanation (points of support) and significance. This is a diagnostic assessment because I have having them write it as a way to assess how well they understand the requirements of writing an academic paragraph. I will use the results of this assessment to see what level of further instruction is required.