We use a broad set of education levels to describe resources, rather than listing a specific grade. This improves the portability of data as grade-level requirements can vary widely from location to location. Using general categories, such as Lower Primary rather than Grade 1, improves the accuracy of resource descriptions.
| Level | Sub-Level | Grade |
| Primary | Preschool | Birth to PreK |
| PK | ||
| Lower Primary | Grade K | |
| Grade 1 | ||
| Grade 2 | ||
| Upper Primary | Grade 3 | |
| Grade 4 | ||
| Grade 5 | ||
| Secondary | Middle School | Grade 6 |
| Grade 7 | ||
| Grade 8 | ||
| High School | Grade 9 | |
| Grade 10 | ||
| Grade 11 | ||
| Grade 12 | ||
| Post-Secondary | Community College / Lower Division | |
| College / Upper Division | ||
| Graduate / Professional | ||
| Career / Technical | ||
| Adult Education | ||
| Informal Education |