Big idea (E2.3, part 2): Ontario's soils vary (largely because of material left by glaciers) and different soils suit different foods: muck soils of the Holland Marsh for vegetables, sandy soils of Norfolk County for fruit and vegetables, loams and clay loams of southwestern Ontario for field crops, clay belts in the north for forage, and thin acidic Shield soils supporting forest and wild blueberries. The Three Sisters show long-standing First Nations knowledge of soil (A3.3); this also shows why soil matters to communities (E1.1).
Indigenous perspectives: The Three Sisters are grown by many Nations; for the Haudenosaunee they are also part of ceremonies and teachings (often called the Three Sisters or "our sustainers"). Manoomin is central to many Anishinaabe communities. Present these as living traditions, not history only. If possible, look for books by Indigenous authors or local Indigenous food programs.
How to help: Shop with your child and read produce labels (A1.1 research). The bean test takes 3 weeks: keep a calendar and measure weekly. It is a fair test (A1.2) if only the soil changes.
Common difficulties: Children may think one soil is "best" for everything. Stress that each plant has needs and the best soil depends on the plant.
Safety: Dry bean seeds are for planting, not eating raw. An adult pokes drainage holes. Keep seeds away from toddlers (choking hazard), and wash hands after handling soil.