I wonder if I can ask her if "we can come up with some bonus problems" to give them if they finish and get restless. If she likes the idea, then offer to create them?
I think this is a good idea. Put the emphasis on the fact that they are finishing early and need more work, not on the fact that the work is too easy.
Therr is a risk she will then give more work attge same level. Maybe a book of logic puzzles they could do together would be OK. Of course this teacher may be oerfectly happy for you to do 3rd grade maths with them or at least turn a blind eye. Any way you can find out? Suggest several options and see what she likes? Games seem non threatening but can be teaching a lot.
Sounds paranoid but my ds6's teacher has upset her boss by letting him get further ahead than the boss would like and the boss is now telling me that she shoukdn't have let him and is basically too inexperienced to be competant.
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