Rice Plot Design Challenge

Fixed area, fixed water, fixed number of seedlings. Design the plot.

The constraints conflict, which is the point. Tight spacing gives more plants and weaker ones. Wide spacing gives strong plants and fewer of them. There is an optimum and children can reason toward it rather than being handed it.

The page has the constraint list, a design grid, a predicted yield calculation and space for the actual result if you grow it. Growing it takes a term and is worth doing at least once, because the gap between predicted and actual is where the real learning sits.