## Wednesday, June 13, 2012

I blogged recently about some of the issues I have with SBG when it comes to reassessments. The other issue that I did not touch upon is equally as thorny. When you are the only one doing Standards Based Grading and you have to give a percentage grade, how do you go about doing it?

The past two years, I have taking my scale and converted it to scores out of ten points.

Basically, I added 5 to each numeric score and made it a score out of 10. The first year, I felt pretty good about where grades ended up. I can't say that this year. I had 2 students who passed Algebra 2 who probably shouldn't have passed the course. I am wondering if I have my scores correlated to the appropriate grades.

In Ohio, we give students a score on their state tests based on the following 5 point scale:
Basic
Limited
Proficient
Accelerated

Now, granted, some of the names are misnomers to me because in order to be "Proficient," you earn about 40% of the possible points on the test. Plus, the skills that are tested (at least for the Ohio Graduation Test) are from 8th through 10th grade and if it's supposed to be a graduation test, I feel it should also test 11th and 12th grade skills. However, I'm not presenting the names as an attempt to argue about the OGTs today.

BUT, I do think I need to possibly change how I grade and stay with the idea of a true 5-point scale that our state testing uses. I am struggling with how to adjust the worth. I figure to drop the "0" and work with 5 true points. Our school grading scale is:
0-65% F
66-74% D
75-84% C
85-92% B
93-100% A
We give percent scores on the report card as well as on progress reports.

The first two should be, in my mind, something along the lines of little or no knowledge and some knowledge. Neither of these scores should be passing. Since 66% is passing, I'm not totally sure how I want to break these up. One thought I have is the lowest should be 5/10 (50%) and the second lowest 6/10 (60%) or 6.5/10 (65%).

The middle score is I think too high currently at 8/10 (80%). I am thinking it should be at 7.5/10 (75%), which is the lowest C in our grading scale. However, if I do that, where do I put the second highest score? 8.5/10 (85%)? 9/10 (90%)? Do my increments really need to be equal? I still want the top score to be 10/10 (100%), but then I still have the issue of what do I do with the students who have the concepts down but make one computational error (whom I tended to give a 4.5 -> 9.5/10 (95%)) or have the idea down except for one minor conceptual error that was not specifically related to the concept being graded. So that brings me back to a 6 point scale rather than 5 points.

druin said...

Here's mine..

3 = Proficient = 8.5/10
2 = Limited Knowledge = 7/10
1 = Minimal = 6/10
0.5 = They tried, but got nothing right = 5/10
0 = Left it blank = 0/10

Our grading scale is 60% = D- and 10 point increments from there

James Cleveland said...

The one I'm currently working with is

5 - Master - 100
4 - Proficient - 90
3 - Journeyman - 75
2 - Apprentice - 60
1 - Novice - 50
0 - Unrated (Blank/Not Turned In) - 0

Lisa said...

James - What is the grading scale at your school? How do you explain the levels to your students?

CalcDave said...

The point of the score (out of 5) is to give the student/parent an idea of where he/she is in understanding the material. For that reason, I think a number might just be confusing. Maybe give them an A, B, C, D, F or some other letter/symbol system. Mine would get a 3/5 and think they got a 60% no matter how much I tried to tell them otherwise. Then the whole grading thing became some sort of mystery they didn't care to figure out.

Also, converting the grade is only as important as giving snapshot views of a student's place in the class. With that in mind, I would always go back at the end of the grading period (quarter, 6 weeks, whatever) and adjust their number grade to match what I felt was closer to their actual understanding in the class. With that in mind, it's always easier to raise their grade at the end than lower it, so when I'd input the individual grades, I'd put them slightly lower than where they might be concretely. Then I could adjust upwards at the end.

Marshall Thompson said...

You have an added challenge of a uniform school-wide grading scale. I'd work with admin on changing that or allowing some flexibility.

Even so, you're stuck with it for now. You intervals have sizes 65/9/10/8/8, which is a little bizarre from where I stand. I think the best option would be to cap your low end at 58%. No student would ever get below that percentage. Then you have intervals of 8/9/10/8/8, pretty close to equal but not quite.

I'd suggest playing around with a linear model with endpoints (0,58) and (5,100), see where the kids land and tinker with that low end or even move beyond a linear model if it's not fitting your needs.

Marshall Thompson said...

By the way, I used to assign words like "proficient" and "mastery" to my numbers because they were so open to interpretation and a number of people challenged me on them.

And then after I did that the district got more specific with what each level meant.

druin said...

Would your principal allow to do the whole "to pass,.must earn at least a 2 on every objective" method?

Anthony said...

I guess the problem with the "to pass, must earn at least a 2 on every objective" would be that if a kid got a 1 on one of 100 objectives... and 5 on the rest, would you fail them?

Would you want a kid with limited knowledge about everything to pass? In your scale, you labeled it "I think you don't know it"... Do you want that kid to pass if you think he doesn't know everything?

I like the 4 point scale that Sam Shah uses:

http://samjshah.com/2010/09/09/first-day-of-201011-introducing-sbg/

He scales it:
0 - left it blank
1 - Weak or no conceptual understanding
2 - You have demonstrated some conceptual understanding
3 - You have a firm grasp of the skill
3.5 - You have mastered the skill but have a few minor (non conceptual error)
4 - You have truly mastered this skill.

I would say that an average of a 3 is a C+, 4 is an A+. I'd say a 2.3ish is a D-.

I'd then use a formula like this:
y=33/1.7*(x-4)+103

To perform a regression between the points: (2.3, 70) and (4, 103)

It would give kids with a 3.6 to 4 an A, 3.1 to 3.5 a B, 2.7 to 3 a C, 2.3 to 2.6 a D.

KristinABC said...

i use
3.5 = proficient 87.5% B
3 = basic 75% C
2 = below basic 50% (attempted)

originally i had it out of 5, but i didn't like that a 4 automatically brought you down to a B-.

When I test there is usually 3 questions on each objective...so if the get all 3 correct, it is a 4, 2 correct is a 3.5 (usually miss the most difficult problem), 1 correct is a 3 (only got the basic problem correct).

Unknown said...

As I plan for the next school year, I am thinking a lot about some format involving Shawn Cornally's Binary Grading:
http://shawncornally.com/wordpress/?p=2489

Basically, for each standard say they have it or don't (proficient or not), and then their grade is the percentage of proficients out of the total number of standards.