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Remote Ready Biology Learning Activities has 50 remote-ready activities, which work for either your classroom or remote teaching.
Useful sites
After a couple of aborted attempts at finding new and interesting sites, I decided to try my own list of sites -- the one I give to my students. While most of these are aimed at high achool chemistry students, I thought that some might satisfy this assignment. I think I found a couple.
You might want to start at: http://bronstein.home.comcast.net/~bronstein/websites.htm
I found that http://www.nettrekker.com/ is very useful since it has a number of exercises for kids to follow up on.
Alsd good is: http://www.loc.gov/rr/scitech/mysteries/
http://www.funsci.com/texts/index_en.htm
This site can get kids thinking about alternative uses for everyday items, which admittedly can be dangerous: http://www.wackyuses.com/uses.html
Some other sites might be of interest, but the above ones, I think, most closely satisfy the assignment.