Unit 06 · Classification & the Kingdoms of Life
With millions of species on Earth, scientists need a way to sort them all. This unit is about classification — grouping living things by the traits they share. You’ll survey the great kingdoms of life, learn how species get their two-part scientific names, and both use and build dichotomous keys to identify organisms. Mastery means you can key out a living thing using its observable traits and explain your choices.
| Criterion | Developing | Proficient | Mastery |
|---|---|---|---|
| Sorting by shared traits | Groups organisms by one surface clue, like color. | Groups by traits but relies on just one at a time. | Sorts living things into groups using several shared, observable traits. |
| The kingdoms of life | Thinks living things are just plants and animals. | Names a few kingdoms but not what sets them apart. | Names the main kingdoms of life and gives a key trait for each at a survey level. |
| Species & scientific names | Doesn’t know living things have scientific names. | Knows names exist but writes them incorrectly. | Explains what a species is and reads a two-part scientific name correctly. |
| Reading a dichotomous key | Can’t follow a key’s yes/no steps. | Follows a key but gets lost on harder branches. | Uses a dichotomous key to identify an unknown organism, step by step. |
| Lab technique (building & using a dichotomous key) | Writes key steps that are vague or don’t split the group. | Builds a key but the questions overlap or leave gaps. | Builds a working dichotomous key with clear yes/no traits and tests it on real specimens. |
| Integration (cross-domain) | Treats the science as isolated facts; makes no cross-domain connection. | Names a link to history, reading, or writing but cannot defend why it matters. | Connects the unit to its anchor across History · Reading · Writing (plus chosen electives) and defends why the connection matters. |
“I keyed out the leaf by asking clear yes/no questions — is the edge smooth or toothed, is it one blade or many? Each answer sent me down one branch until only one plant was left. Then I checked its scientific name to be sure.”
“I sorted them by color because that’s easy. A key is just a list, right? I’m not sure why they have those long Latin names.”
You demonstrate this unit by building and using dichotomous keys — sorting real specimens by their traits and explaining each choice aloud, not on a multiple-choice test. This unit also leads into the timed classification challenge, where you key out organisms under time pressure. A criterion counts as mastered only when you can both make the identification and defend the traits behind it. Mastery is demonstrated, not awarded.
A 5-page clipboard packet — unit overview, key terms, the mastery rubric, anchor examples, and a score sheet you can print and grade against.