"participation mark" is a correct and usable phrase in written English.
You can use it to refer to a mark given to a student for participating in a class, usually in addition to the mark they received for their work (e.g. a quiz or assignment). For example: Every student in the class was awarded a participation mark for their contributions to the discussion.
"We'll feel like we have legitimate success when not only is our national team achieving what it's capable of, but also when we're at that 50, 60, 75, 100,000 participation mark.
The BEDCI was administered in the same way in all five classes; students were given a bonus participation mark (0.5% bonus mark for completing each of the pre- and posttests) but were otherwise neither rewarded nor penalized for their performance.
Digitally-savvy, circumventing traditional media and operating in an unchartered technological era, their participation marks something of an unknown for party leaders.
Thirteen contributors are students from the East Side Middle School in New York, and their participation marked one of the first times that teenagers have co-authored a scientific article alongside researchers with advanced degrees.
"Give participation marks two weeks at a time". Caramel crunch?
Their 2017 Atlanta Summit featured Virgin Founder Richard Branson and CNN Commentator Van Jones, whose celebrity participation marks a sign of greater awareness of the issue.
Their participation marked their fourth Olympic appearance.
Their participation marked their second Commonwealth Youth Games appearance.
Brendan's participation marked his second Olympic appearance, having competed in the 2004 Summer Olympics.
His participation marked his second appearance at the Olympics, with his first being at the 2004 Summer Olympics in Athens.
Their participation marked their sixth Olympic appearance, and included the smallest number of athletes that had ever represented Aruba in its history.
