File Structure
The JSON files available for download reflect the underlying data schema. Accordingly they are conventionally normalized. The language preferentially draws from the canonical documents:
- NRC K-12 Framework for the disciplines, disciplinary core ideas, component ideas, and subideas
- Appendix F for the Science and Engineering Practices
- Appendix G for the Crosscutting Concepts
- Appendix H for the Nature of Science
- Appendix J for ETS Connections
There are twenty files:
- Two central files, one describing the core portions of the performance expectation and one describing the evidence statements;
- Four sets of two files each describing the two-level hierarchies of the Science and Engineering Practices (SEP), Crosscutting Concepts (CCC), Connections to Engineering, Technology, and Applications of Science (ETS Connections, or ETS), and Nature of Science (NOS);
- One set of four files describing the four-level hierarchy of the Disciplinary Ideas (DCI): The Discipline, Core Idea, Component Idea, and the Subidea;
- Five Links files describing n:n relationships of performance expectations and SEP, CCC, NOS, ETS, and DCI;
- One Topics file that doesn’t fit anywhere else.
Some evidence statements include equations and other symbols, which have been set in $\LaTeX$ and rendered with $\KaTeX$. They are MS-PS2-2, MS-PS3-1, HS-ESS1-4, HS-ESS3-3, HS-PS2-3, HS-PS2-4, and HS-PS4-1, plus HS-ESS2-4, HS-ESS3-6, HS-ETS1-1, and HS-LS1-7. The last four use $\LaTeX$ merely to subscript the “2” in “CO${}_2$”. You can, of course, edit the download file to implement a different solution.
performance_expectations.json
Core PE data – 208 records
| Column | Type | Description |
|---|---|---|
| id | int | Primary key |
| code | string | PE code (e.g., “HS-PS1-1”) |
| topic_id | int | FK to topics |
| grade_level | string | K, 1-5, MS, or HS |
| description | string | Full PE statement |
| clarification_statement | string | Optional clarification |
| assessment_boundary | string | Assessment limits |
| source_document | string | Source PDF filename |
evidence_statements.json
Evidence statements for each PE
| Column | Type | Description |
|---|---|---|
| id | int | Primary key |
| pe_code | string | PE code |
| content | JSON | Structured evidence statement content |
SEP (Science & Engineering Practices) – Two-Level Hierarchy
sep/practices.json
Top-level SEP practices – 8 records
| Column | Type | Description |
|---|---|---|
| id | int | Primary key |
| code | string | Practice code (SEP1-SEP8) |
| number | int | Practice number (1-8) |
| name | string | Practice name |
| abbreviation | string | Short abbreviation |
| description | string | Practice description |
sep/subpractices.json
SEP subpractices (grade-banded) – ~200 records
| Column | Type | Description |
|---|---|---|
| id | int | Primary key |
| code | string | Subpractice code (e.g., “SEP1-K2-a”) |
| sep_id | int | FK to practices |
| grade_band | string | Grade band (K-2, 3-5, 6-8, 9-12) |
| is_progression | int | 1 if progression statement |
| description | string | Subpractice text |
| comment | string | Internal comment |
| sort_order | int | Display order within grade band |
CCC (Crosscutting Concepts) – Two-Level Hierarchy
ccc/concepts.json
Top-level CCC concepts – 7 records
| Column | Type | Description |
|---|---|---|
| id | int | Primary key |
| code | string | Concept code (CCC1-CCC7) |
| number | int | Concept number (1-7) |
| name | string | Concept name |
| abbreviation | string | Short abbreviation |
| description | string | Concept description |
ccc/subconcepts.json
CCC subconcepts (grade-banded) – 81 records
| Column | Type | Description |
|---|---|---|
| id | int | Primary key |
| code | string | Subconcept code (e.g., “CCC1-K2-a”) |
| ccc_id | int | FK to concepts |
| grade_band | string | Grade band (K-2, 3-5, 6-8, 9-12) |
| description | string | Subconcept text |
| sort_order | int | Display order within grade band |
ETS (Engineering, Technology, and Society Connections) – Two-Level Hierarchy
ets/core_ideas.json
Top-level ETS core ideas – 2 records
| Column | Type | Description |
|---|---|---|
| id | int | Primary key |
| code | string | Core idea code (ETS-CONN1, ETS-CONN2) |
| name | string | Core idea name |
| abbreviation | string | Short abbreviation |
| comment | string | Internal comment |
ets/statements.json
ETS statements (grade-banded) – 25 records
| Column | Type | Description |
|---|---|---|
| id | int | Primary key |
| code | string | Statement code (e.g., “ETS-CONN1-K2-a”) |
| core_idea_id | int | FK to core_ideas |
| grade_band | string | Grade band (K-2, 3-5, 6-8, 9-12) |
| description | string | Statement text |
| comment | string | Internal comment |
NOS (Nature of Science) – Two-Level Hierarchy
nos/categories.json
Top-level NOS categories – 8 records
| Column | Type | Description |
|---|---|---|
| id | int | Primary key |
| code | string | Category code (NOS1-NOS8) |
| number | int | Category number (1-8) |
| name | string | Category name |
| abbreviation | string | Short abbreviation |
| associated_with | string | Associated dimension (Practices or Crosscutting Concepts) |
| comment | string | Internal comment |
nos/understandings.json
NOS understandings (grade-banded) – 86 records
| Column | Type | Description |
|---|---|---|
| id | int | Primary key |
| code | string | Understanding code (e.g., “NOS1-K2-a”) |
| category_id | int | FK to categories |
| grade_band | string | Grade band (K-2, 3-5, 6-8, 9-12) |
| description | string | Understanding text |
| sort_order | int | Display order within grade band |
| comment | string | Internal comment |
DCI (Disciplinary Core Ideas) – Four-Level Hierarchy
dci/disciplines.json
Top-level DCI disciplines – 4 records
| Column | Type | Description |
|---|---|---|
| id | int | Primary key |
| code | string | Discipline code (PS, LS, ESS, ETS) |
| description | string | Discipline name |
| sort_order | int | Display order |
dci/core_ideas.json
DCI Core Ideas (2nd level) – 13 records
| Column | Type | Description |
|---|---|---|
| id | int | Primary key |
| discipline_id | int | FK to disciplines |
| code | string | Core idea code (e.g., “PS1”, “LS2”) |
| description | string | Core idea name |
dci/component_ideas.json
DCI Component Ideas (3rd level) – 44 records
| Column | Type | Description |
|---|---|---|
| id | int | Primary key |
| core_idea_id | int | FK to core_ideas |
| code | string | Component code (e.g., “PS1.A”, “LS2.B”) |
| description | string | Component idea name |
dci/subideas.json
DCI Subideas (4th level, grade-banded) – ~450 records
| Column | Type | Description |
|---|---|---|
| id | int | Primary key |
| code | string | Subidea code (e.g., “ESS1.A-MS-a”) |
| grade_band | string | Grade band (K-2, 3-5, 6-8, 9-12) |
| component_idea_id | int | FK to component_ideas |
| description | string | Subidea text |
| boundary_note | string | Optional boundary note |
| comment | string | Internal comment |
Links Files – PE to Dimension Relationships
links/pe_sep_links.json
Junction table linking PEs to Science & Engineering Practices
| Column | Type | Description |
|---|---|---|
| id | int | Primary key |
| pe_id | int | FK to performance_expectations |
| subpractice_id | int | FK to sep/subpractices |
links/pe_ccc_links.json
Junction table linking PEs to Crosscutting Concepts
| Column | Type | Description |
|---|---|---|
| id | int | Primary key |
| pe_id | int | FK to performance_expectations |
| subconcept_id | int | FK to ccc/subconcepts |
links/pe_nos_links.json
Junction table linking PEs to Nature of Science connections
| Column | Type | Description |
|---|---|---|
| id | int | Primary key |
| pe_id | int | FK to performance_expectations |
| understanding_id | int | FK to nos/understandings |
links/pe_ets_links.json
Junction table linking PEs to ETS (Engineering) connections
| Column | Type | Description |
|---|---|---|
| id | int | Primary key |
| pe_id | int | FK to performance_expectations |
| connection_id | int | FK to ets/statements |
links/pe_dci_links.json
Junction table linking PEs to Disciplinary Core Ideas
| Column | Type | Description |
|---|---|---|
| id | int | Primary key |
| pe_id | int | FK to performance_expectations |
| subidea_id | int | FK to dci/subideas |
| is_secondary | int | 1 if secondary DCI |
| cross_reference | string | Cross-reference to other PEs |
Other Files
topics.json
Topic bundles for PEs – 54 records
| Column | Type | Description |
|---|---|---|
| id | int | Primary key |
| grade_level | string | Grade level (K, 1-5, K-2, 3-5, MS, HS) |
| description | string | Topic description |
| category | string | Grade name or discipline code (PS, LS, ESS, ETS) |