Schoolyard Bioblitz: Count Living Things and Settle 'Is a Spider an Insect?'

You don’t need a nature reserve to do real ecology. A patch of grass and a loop of string are enough. A schoolyard “bioblitz” gets students counting living things and asking how scientists decide what belongs in which group.

Part 1: the one-metre square

You need: a 4 m piece of string tied in a loop (a knot every metre), flat stones or pegs, hand lenses, clipboards and pencils.

1. Lay the string in a square, 1 m on each side, in one spot. Use stones to hold the corners.
2. Predict how many kinds of living things you’ll find.
3. Look carefully, using the hand lens, and record every kind you find: plants, insects, worms, moss, fungi, spiders. Don’t take anything, don’t touch animals and put back anything you move.
4. Sort the findings into living, once living (a dead leaf, a feather) and never alive (a stone, a bottle cap).
5. Repeat in a different spot, such as sunny grass and a shady corner, and compare.

You’ll often find more in the shady, damp square. That’s data you can discuss: what do living things need?

Our lesson Who lives in our schoolyard? has teams do exactly this.

Part 2: is a spider an insect?

Ask the class. Most say yes. Here’s how scientists decide: by features, not looks.

Feature	Insect	Spider
Legs	6	8
Body parts	3 (head, thorax, abdomen)	2
Antennae	Yes	No
Wings	Often	Never

Spiders are arachnids, a different group, together with scorpions, mites and ticks. Insects, such as beetles, ants and flies, are another group. Both are invertebrates, animals without backbones, and both are arthropods.

A sorting game

Make a set of animal cards (a bat, a dolphin, a penguin, a platypus, a snail, a frog, a spider, a beetle and so on). Students sort them using questions:

1. Does it have a backbone?
2. Is it a fish, amphibian, reptile, bird or mammal?
3. If no backbone: does it have six legs and three body parts?

Tricky cards make good discussion. A bat flies but is a mammal. A dolphin lives in water but breathes air and feeds its young milk. A penguin is a bird that swims. A platypus is a mammal that lays eggs.

Then turn the sorting rules into a yes-or-no key. That’s how real field guides work.

Try Is a spider an insect? for the full activity.

Be a good guest

• Look, don’t collect.
• Return rocks and logs as you found them.
• Watch for stinging insects and wasp nests. A teacher checks the area first.
• Check for allergies and wear gloves for anything that might sting or bite.
• Wash hands after.

Keep exploring

These are the first two lessons in Who Lives Here?, which continues with Does every animal grow up the same way? and Who can live here and who can’t? Sign up for three lessons free.