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Meeting 3: predict, run, explain

These short activities connect the slides to the full workshop. They are ungraded. Use one as a five-minute class demonstration; use the other for a warm-up or independent practice. They replace part of the existing demonstration time.

Before every run, write one prediction. Afterward, record one row or screen that supports or contradicts it. Then make one change and explain the result without reading the code aloud.

1. Direction stays fixed. The key changes.

Open the editable example. The editor supplies startup and output code so you can focus on the experiment. Expand Supplied setup and run lines to see those lines; downloaded JS includes them.

Predict: For ←←→←←, which key is correct in each group?

Change and test: Change group from “A” to “B” and rerun. Then change one arrow string and its target direction together.

Inspect: Read the center arrow independently. The expected key follows the group mapping; the target direction does not change.

Write three short notes:

2. Pass, repeat, or stop.

Open the editable example. The editor supplies startup and output code so you can focus on the experiment. Expand Supplied setup and run lines to see those lines; downloaded JS includes them.

Predict: Will exactly three correct answers out of four pass?

Change and test: Try 2/4 then 3/4. Rerun and fail both attempts. This small demo permits two attempts; the workshop permits three.

Inspect: Filter by task and attempt. Passing creates one test row; failing at the maximum creates no test rows.

Write three short notes:

Transfer to the workshop

Draw the full flanker routes with three allowed attempts and eight test trials. Mark where practice feedback belongs. Write expected practice/test counts for pass-first, fail-then-pass, and fail-all routes.

Diagnose one fault

Practice stops after its maximum attempts, then the next timeline node always runs test.

Explain the cause and the smallest useful test. Do this before reading the check below.

Check your reasoning after an attempt

Example 1: The center points right. Group A uses J; group B uses F. A URL parameter can carry this assignment but does not balance how many people receive each group.

Example 2: 3/4 passes because the condition is >= 0.75. Failing once then passing creates eight practice rows and one test row. Failing twice creates eight practice rows and zero test rows.

Fault: The bound only stops repetition. Add a conditional test gate based on passing practice, and verify zero test rows in the fail-all export.

Keep a useful record

Download edited JS if you want to keep your change; a reset or refresh replaces it. For experiment examples, download JSON after the run. Source packs include HTML, the initializer, libraries, and assets: small-example source pack. These files are for learning; the workshop remains the core task.