Introduction to Variables

Description

Uses the metaphor of a "mystery box" to explain that a variable is a placeholder that can hold different values. Students see the same expression x + 2 evaluated for x = 3 and x = 7, building intuition before formal algebra.

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Phases

#	Phase Name	Duration	Description
1	Mystery Box	7s	Show a labeled box with "x" on it. Ask: what could x be?
2	Reveal x = 3	8s	Animate the box opening to reveal 3 dots inside. Show x = 3 on screen.
3	Expression x + 2	8s	Show box (x=3) plus 2 more dots. Count to get 5. Show x + 2 = 5.
4	Change to x = 7	8s	Close box, change to 7 dots. Recompute x + 2 = 9.
5	Summary	7s	Define variable: a symbol that can hold any value. Show general form.

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Layout

+------------------------------------------------------+
|     [Title: Introduction to Variables]               |
|                                                      |
|        +--------+                                    |
|        |   x    |   ← Mystery Box                   |
|        +--------+                                    |
|                                                      |
|   [Dots / values revealed here]                      |
|   [Expression display]                               |
|   [Equation result]                                  |
+------------------------------------------------------+

Area Descriptions

Area	Content	Notes
Top	Title	Persistent
Center	Mystery box graphic	Animates open/close
Below box	Dots representing value	Count shown
Bottom	Equations and annotations	Per phase

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Assets & Dependencies

• Fonts: LaTeX / sans-serif
• Colors:
  • Box: GOLD / YELLOW
  • x label: WHITE
  • Dots (x value): BLUE
  • Extra dots (+2): GREEN
  • Equations: WHITE
  • Background: #1a1a2e
• Manim version: ManimCE 0.19.1

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Notes

• The box is a Square with a label; "opening" is shown via FadeOut box and FadeIn dots.
• Dots are arranged in a row for easy counting.
• Changing x is visually distinct (different color flash).