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Remote Ready Biology Learning Activities has 50 remote-ready activities, which work for either your classroom or remote teaching.
couple of good sites on measurement and scale
In the late 50's an MIT undergrad was used to measure the Harvard Bridge over the Charles River. It is a nice application of 'what is measurement?"
Once you walk you kids through even just a part of the 1000 yard model of the universe, the first 5 planets takes about 150 yards if I remember correctly, you will open their eyes.