Converting SBG to Traditional/Percentage Grades

After much thought, I've worked out how I will convert SBG to letter grades, and it is actually quite simple.  First, I began with the breakdown established at the beginning of the year.  Luckily, we were on the right track to develop a grading system that reflected students' proficiency breakdown.  Our categories include Listening (20%), Reading (20%), Writing (20%), Speaking (20%), Culture (10%), and Citizenship (10%). (The citizenship grade includes things like attendance, participation, work/homework, etc.)  This breakdown reflects our priority on developing students who are proficient in using the language rather than simply reflecting tests, quizzes, and homework.  I used this same breakdown in my SBG breakdown.  For my SBG, I used scores of 1-4, with 4=Advanced ("A"), 3=Proficient ("B"), 2=Basic ("C"), and 1=Below Basic ("D/F").  A student will receive a score of 0 for items simply not compelted.

The steps for determining letter grades from SBG assessments are as folows:

1. Determine scores for each standard.
• Here, I have to decide which scores I am going to count - in my case, I think I will only count the most recent score (which will likely be the one that shows up on my final summative exam).
2. Determine average scores for each category.
• Average scores within each standard which I determined I wanted to count from the last step.  For example, if I had 4 reading standards and a particular student received the scores of 3, 3, 4, 4, so their reading average will be 3.5.
3. Determine overall score from weighted formula.
• In my case, this will be: Listening*2+Reading*2+Writing*2+Speaking*2+Culture(*1)+Citizenship(*1)
4. Round this score to the nearest 10.
• The raw scale is biased downward, so the score needs to be rounded.
5. Add this score to 50 and you have the final overall grade in a percentage!
• You will only end up with scores that end in 0 (i.e. 90%, 80%, 70%.... etc.), so a letter grade without a +/- is assigned.