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Remote Ready Biology Learning Activities has 50 remote-ready activities, which work for either your classroom or remote teaching.
Baby Einsteins
The Baby Einsteins link is phenomenal with the classic discrete mathematics topic (four-color map problem), 2D triangular fractals (Sierpinski traingle/gasket), Conway's Game of Life (2D Cellular Automata), but there are plenty of these!
These type of investigations are beyond math ... well not just math anymore. These use very simple rules ... so they are grade independent lending these type of excercizes to spiraliing. Some of the math textbook vendors have added a chapter on discrete math in their textbooks, but they tent to be cursory.