I would like to enable New Gradebook for it's advanced functionality but I am in the middle of a semester. Will changing this setting now affect any of the grades I have in my course?
My rule has always been, "Make no changes mid-term unless absolutely necessary!"
I have not experimented deeply with the new gradebook, but I did learn one thing in this community that might be very important to your question - if you set certain new features in the new gradebook, you cannot revert to the old gradebook! That is quite enough to scare me off from making that change mid-term.
I think your best bet is to read the discussions and ask your question at New Gradebook Users Group
There are folks in there who are making full use of the new gradebook.
I'm with Kelley unless it is absolutely mission critical we don't made any major changes like enabling a new feature unless there just isn't away to avoid it during the middle of a term.
If you are set on making this change I would suggest turning it on in your Beta or Test environments and doing some regression testing to ensure that it doesn't seriously affect anything.
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