At-Home Lab Guides: Real Science with Household Materials

The science: Red cabbage contains anthocyanin, a natural pigment that changes color in acids (turns red/pink) and bases (turns blue/green/yellow). This is the same principle chemists use with pH indicators. Real pH indicators are how chemists tested everything from swimming pools to industrial chemical baths before electronic meters existed.

1. Chop cabbage coarsely. Place in a bowl. Pour boiling water over it and let sit 15 minutes. Strain the purple liquid — this is your indicator.
2. Pour 2 tablespoons of indicator into each cup.
3. Add one substance to test to each cup (about 1 tablespoon).
4. Observe and record color change immediately.
5. Rank substances from most acidic to most basic based on color.

The documented history of lead in water pipes in Flint, Michigan (2014-2019) is partly a chemistry story. Lead dissolves more easily in acidic water. How does what you learned today connect to that documented public health crisis?

1. Pour layers slowly in this order (pour down the side of the glass): honey, dish soap, colored water, vegetable oil, colored alcohol.
2. Wait 2 minutes for layers to settle. Observe and draw the layers.
3. Drop one small object at a time. Record where it settles.

Sketch the layers in order from bottom to top, with labels:

For each object dropped, record where it settled and calculate whether its density is greater than or less than the liquid it sits on:

Density = mass / volume. If a 5g grape has a volume of 4.5 mL, what is its density? _____________ g/mL. Water's density is 1 g/mL. Will the grape float or sink in water? _____________ Was your calculation correct? _____________

Ships are made of steel, which is denser than water. How do they float? Connect what you observed in this experiment to the engineering principle that makes ships possible:

Setup — 4 conditions, one variable changed in each:

Cup A: Normal — soil, water, sunlight (control)
Cup B: No light — cover completely with foil after planting
Cup C: No water — soil and light, but no watering
Cup D: Scholar's choice — change one variable of your choosing (different soil, salt water, different location)

Food deserts are documented areas where fresh produce is unavailable or unaffordable — disproportionately affecting Black and low-income communities. What does your experiment tell you about what communities would need to grow food locally? Name one specific resource and one specific challenge:

1. Collect one cup of soil from each of three locations — try to vary: near a building, under a tree, open ground.
2. Fill each jar halfway with soil. Add water until the jar is 3/4 full. Shake vigorously for 30 seconds.
3. Let the jars sit undisturbed for 1 hour, then observe the settled layers.
4. Measure the height of each layer (sand sinks first, then silt, then clay on top).

For each sample, record: location, color of soil, smell (yes, document it), water clarity after settling, and layer measurements:

Sandy layer height: _____ cm   Silt layer: _____ cm   Clay layer: _____ cm   Total depth: _____ cm

Which sample had the most clay? _____________ Which had the most sand? _____________

A soil high in clay drains slowly. A soil high in sand drains quickly. Which would be better for a garden? Why?

The documented history of Black land ownership in America — including the loss of over 12 million acres between 1910 and 1997 (USDA data) — is partly a soil and geography story. Access to good farming land was not equally distributed. What does your soil analysis tell you about the agricultural value of the land near your home?