Congratulations Ian on discovering the value of self
assessment so early in your teaching career. I learned
a lot about grading by having the students grade their
work first. I would say 90% of the time their grades
were the same as ones I would have given (rarely
higher). When you make the objectives clear, students
are able to see how well those objectives are met. In
a lesson, drawing skills was only one objective -
color planning was another - and so forth.
Some students would score very high on one objective -
but may fall short on another - and still be able to
get a high grade on the project.
Don't set your students up for failure. They will quit
working for you. Design your lessons so that all
children can at least get a passing grade if they do
the assignment. Let them know what you expect for B
and A work - and make them work for the grade.
I have lots of different forms I used over the years
if you are interested - but it sounds like you have
found a system that works for you. You can do
elementary self assessment very easily, too. Student
always want to know right away what their grade is.
Have them tell you what they think it is is and ask
they why they think that (just a verbal assessment).
You can get through a whole class pretty quickly while
they are working. You can then tell them why your
assessment is higher or lower. I could usually
remember what I said to each kid - but you might want
to have your grade book handy just in case you can't.
Kids know when their behavior interferes with their
grade - Most of you can not grade behavior - but find
a way to grade participation. Disruptive behavior
affects everyone's grades one way or another. No one
ever questioned my effort and participation grades -
especially when the kids graded that themselves.