Teaching resource · secondary

Count a political archive without inventing certainty

A 50-minute lesson about counting units, evidence, and unknowns, based on release 2026-07-31.1.

Time: 50 minutes
Grade: 9–12
Subjects: Civics, history, mathematics, media literacy
Materials: Access to the manifest and events and participants tables

Learning objectives

Distinguish an event, person, and participation.
Calculate and name a denominator.
Explain why “unknown” is useful data.
Assess whether a sentence is supported by a data release.

Teacher preparation

Download or open the manifest, events.csv, and participants.csv. Arrange pairs or groups of three. No prior knowledge of a particular political event is required.

Procedure

0–8 min · NoticePresent six manifest numbers: 218 events, 208 named participations, 206 people, 10 unresolved groups, 40 events with a source link, and 0 verified events. Students write two differences they notice.
8–18 min · DefineEach group proposes a definition for event, person, and participation. Compare it with the published counting rules.
18–33 min · Test headlinesClassify the four worksheet statements as supported, misleading, or insufficiently evidenced. Every answer must cite a column or measure.
33–43 min · RecalculateAsk: what share of leads has at least one source link? Students calculate 40 ÷ 218 ≈ 18.3%, then explain why the result is not the share of “true” historical events.
43–50 min · Exit ticketIn two sentences, explain why replacing ten unresolved groups with ten people would be a data-model error.

Student worksheet

1. “The dataset contains 218 politicians.”
□ supported □ misleading □ insufficient evidence
2. “The release contains 218 inherited event leads.”
□ supported □ misleading □ insufficient evidence
3. “18.3% of all Canadian affiliation changes are proven.”
□ supported □ misleading □ insufficient evidence
4. “Ten collective events still require participant research.”
□ supported □ misleading □ insufficient evidence

Answer guide

1: misleading—the number describes events, not people. 2: supported by the manifest. 3: insufficient—the denominator is the inherited corpus, not all Canadian history, and a link is not complete evidence. 4: supported by participant_resolution_status.

Accommodations

Provide the numbers as a printed table; read instructions aloud; allow oral or drawn responses; do not assess partisan vocabulary. CSV files are optional when manipulating them creates a barrier.

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Procedure

0–8 min · NoticePresent six manifest numbers: 218 events, 208 named participations, 206 people, 10 unresolved groups, 40 events with a source link, and 0 verified events. Students write two differences they notice.

8–18 min · DefineEach group proposes a definition for event, person, and participation. Compare it with the published counting rules.

18–33 min · Test headlinesClassify the four worksheet statements as supported, misleading, or insufficiently evidenced. Every answer must cite a column or measure.

33–43 min · RecalculateAsk: what share of leads has at least one source link? Students calculate 40 ÷ 218 ≈ 18.3%, then explain why the result is not the share of “true” historical events.

43–50 min · Exit ticketIn two sentences, explain why replacing ten unresolved groups with ten people would be a data-model error.

Student worksheet

1. “The dataset contains 218 politicians.”

□ supported □ misleading □ insufficient evidence

2. “The release contains 218 inherited event leads.”

□ supported □ misleading □ insufficient evidence

3. “18.3% of all Canadian affiliation changes are proven.”

□ supported □ misleading □ insufficient evidence

4. “Ten collective events still require participant research.”

□ supported □ misleading □ insufficient evidence