# Shadow Window — supplied source card

| Field | Actual information |
| --- | --- |
| Name / source ID | **Shadow Window**, S5-SHADOW-WINDOW-01 |
| Creator | SubjectNest by NeuroForgeIO Pty Ltd, created with Codex assistance |
| Date | 30 September 2026 |
| Type | Original computer-created ideal point-source teaching model; saved diagrams and exact descriptions, not a human field report or photograph |
| Documented author purpose | Make straight-path blocking visible so learners can choose a shadow question/design and distinguish an idea prediction from an actual lamp observation |
| Context | This Year 5 Science teaching resource; no fictional community/cultural importance, human investigator or audience effect |
| Licence | Original expression CC BY 4.0; acknowledge title/creator/date/licence and adaptations |

The ordinary [straight-path aid](print/straight-path.pdf) has a model point source `(0,0)`, an opaque vertical bar at `x=4` from `y=-1` to `y=1`, and a screen at `x=8`. Two ideal straight rays touch the bar's endpoints and reach screen `y=-2` and `y=2`. Its model shadow span is four **arbitrary model units**. These are not centimetres, actual apparatus directions or learner measurements. The [change-one aid](print/change-one.pdf) retains source/screen/bar size, changes bar `x=4` to `x=2`, and its ideal screen span becomes eight arbitrary units. No ratio calculation is required of the learner.

A lamp may have an extended luminous source. Ambient light, alignment, distance and unclear edges can affect the actual view. Do not copy model numbers into an actual-data table. If a real observation does not fit the simplified diagram, keep the observation and consider the model/setup's limits.

## Encounter, purpose and actual response

Offer this card and a chosen exact diagram/description only when useful. Ask “What does this idea show? What would you like to try?” Record an actual learner response if one occurs, the resource encountered and access/help. The printed diagram existing is not learner understanding or an actual experiment. The maker purpose above is documented intent; it does not prove that a learner, teacher or audience achieved that effect.

The learner may use, change or reject this model, choose another locally appropriate attributed source or develop an own model. Mark a photograph as a photograph, a live view as an actual view, a person's description as an attributed account, and a drawn ray diagram as a model. Source description alone does not supply missing measurements. No human-endeavour breadth or cultural account is invented from this original resource.