Google classroom overall grade is skewed!

[pinkrocker]

Can you help, the last 3 weeks work is in and marked. Some children only did one task, if they got all the answers right, GC gives them an overall grade of 100%. Others completed all the tasks and for instance may have got 90% correct but they get a worse overall grade from GC. Any ideas where I've gone wrong?

You need to enter a zero grade for the tasks they didn't do if you want an average grade surely.

Thank you, I'll try that (should have realised!)
And there's still work being sent in late...how long do I give them!