Absolutely address it now! Who knows what this teacher will cook up for the next study unit. I would want to have my ducks in a row before the grades for this unit comes out, and she starts another one. I have no idea how these things work these days, only having a 2 year old....and not being there yet. But I would imagine that if things are this far off the rails (videos?
?? for several days in a row, while there are still assignments being done? Are they even scientifically related to the unit they are studying?) that the principal and a few others may need to sit in on class to find out whats going on.
I would be on this by next wednesday at the latest. I would want the weekend to write down a timeline, gather emails chronologically, assemble any syllabi and parent handouts and your son's current work, find out what in tarnation these videos are (are they taking notes or being asked questions about the videos?) get all my evidenciary ducks in a row, and perhaps talk to the Mother of your son's classmate and feel her out. Then I would be requesting a meeting with the principal right after that. OP is 6th grade in the elementary schools where you are, or is this a middle school (grades 6-8). Do the teachers work in teams?
I don't mean necessarily to go in looking for the teachers blood (although I would be plenty ticked off) but I would want to give the principal the most thorough package to start with so this doesn't drag out for the next 3 months.