Addition & Subtraction on a Number Line

Description

Show a number line from 0 to 20 with a colorful arrow hopping right for addition and left for subtraction.
Two worked examples are shown: 5+3=8 (three hops right) and 8-3=5 (three hops left).
Each hop is animated individually with equation labels updating live.

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Phases

#	Phase Name	Duration	Description
1	Title card	3 s	Title "Addition & Subtraction" fades in
2	Number line intro	4 s	Number line 0–20 draws; tick marks and labels appear
3	Addition example	12 s	Arrow starts at 5; hops right 3 times to 8; equation 5+3=8 shown
4	Subtraction example	12 s	Arrow starts at 8; hops left 3 times to 5; equation 8-3=5 shown
5	Summary	4 s	Both equations shown side-by-side; fade out

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Layout

+--------------------------------------------------+
|        Addition & Subtraction on a Number Line   |
|                                                  |
|   [equation label: 5 + 3 = ?]                   |
|                                                  |
|   <----number line 0 to 20---->                  |
|        ^hop  ^hop  ^hop                          |
|   [arrow/dot traveling along number line]        |
+--------------------------------------------------+

Area Descriptions

Area	Content	Notes
Top banner	Animation title	Large, white, sans-serif
Middle label	Current equation, e.g. "5 + 3 = ?"	Bright yellow MathTex
Center	Number line with ticks 0–20	Horizontal, spans most of frame
Hop arrows	Small arcs above number line	Cyan for addition, red for sub
Moving marker	Filled circle on number line	Bright green

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Assets & Dependencies

• Fonts: LaTeX (MathTex), Manim default sans-serif (Text)
• Colors: YELLOW (equations), CYAN (addition hops), RED (subtraction hops), GREEN (marker)
• Background: #1a1a2e
• Manim version: ManimCE 0.19.1

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Notes

• Hops are implemented as arcs (ArcBetweenPoints) drawn one at a time.
• Number line uses Line + tick marks drawn as short vertical Lines.
• The marker (dot) uses .animate.move_to() for smooth travel.
• Keep all tick labels small so they don't crowd the frame.