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newsletter-subject-lines skill

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This skill crafts ten plus OpenEd subject lines using proven formulas and a systematic evaluation to maximize opens.

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SKILL.md
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---
name: newsletter-subject-lines
description: Write newsletter subject lines for OpenEd Daily using 15 proven formulas + 10 Commandments evaluation. Generate 10+ options, select best through systematic criteria.
---

# Newsletter Subject Lines

Write subject lines that get opens.

**Core Philosophy:** 80% of email performance comes from the subject line. Generate 10+ options, evaluate systematically, select best.

**Key constraint:** 35-50 characters ideal (mobile preview). Be clear even when truncated.

---

## The 3-Phase Workflow

### Phase 1: Identify Core Value

**What's the one thing that makes this newsletter worth opening?**

Ask:
- What's the most surprising insight?
- What problem does this solve?
- What will readers learn they didn't know?
- What would make someone forward this?

### Phase 2: Generate 10+ Options

Use multiple patterns below + formulas from `references/10-commandments-checklist.md`:
- Try 3-4 different patterns
- Apply sticky techniques from `references/sticky-sentence-techniques.md`
- Test with/without numbers

### Phase 3: Evaluate & Select

Apply evaluation from `references/newsletter-subject-lines-analyzed.md`:
- Score top 5-7 options with 10 Commandments (aim for 4-6)
- Use 4 U's test (Useful, Urgent, Unique, Ultra-specific)
- Final check: Would YOU open this? Would Sarah forward it?

---

## Core Patterns (With Examples)

### 1. Number + Why
Legitimizes with scale, creates curiosity about reasoning.

- "Why 1.5 million students are in microschools now"
- "83% of parents agree: schools aren't preparing kids for AI"
- "The $1,200 your ESA can actually cover"

### 2. Contrast / This vs That
Challenges assumptions with clear binary.

- "The gap that matters isn't algebra. It's initiative."
- "Small schools. Big difference."
- "Credentials vs Community: What actually helps kids thrive"

### 3. Contrarian Truth
Says what's obviously true but rarely said.

- "You don't need permission to start a school"
- "The other kind of testing (the one that actually works)"
- "What if school just... ended earlier?"

### 4. Curiosity Gap
Promises to reveal something specific.

- "What public schools don't want you to know"
- "The education trend public schools fear"
- "The real reason homeschool kids outperform"

### 5. Named Person + Insight
Borrowed authority from someone interesting.

- "Ken Danford quit teaching to prove schools are optional"
- "What Jason Skycak learned tutoring 10,000 hours"
- "She homeschools 5 kids and runs a business. Here's how."

### 6. Challenge + Data
Pattern interrupt backed by evidence.

- "Half of Prenda's guides have no credentials. Here's why it works."
- "Students who test themselves retain 80% more. Schools still don't do it."
- "4-day school weeks work. 900 districts prove it."

---

## Sticky Techniques (Use Sparingly)

Make phrases memorable and quotable.

**Contrast:** "Small schools. Big difference." | "To be everywhere is to be nowhere"

**Symmetry:** "Read for awareness. Write for understanding."

**Alliteration:** "Specificity is the secret" | "Practice produces permanence"

**Rhythm:** Two short parallel phrases that feel balanced

---

## OpenEd Swipe File

Real subject lines that performed well:

| Subject Line | Pattern |
|--------------|---------|
| "Why 1.5 million students are in microschools now" | Number + Why |
| "The gap that matters isn't algebra. It's initiative." | Contrast |
| "Small schools. Big difference." | Sticky (Contrast + Rhythm) |
| "You don't need permission to start a school" | Contrarian Truth |
| "What testing actually works (it's not SATs)" | Curiosity Gap |
| "The getting by trap" | Label (names phenomenon) |
| "83% of parents agree" | Number + Validation |
| "Credentials vs Community" | This vs That |

---

## Workflow

1. **Identify the core insight** - What's the one thing that makes this newsletter worth opening?
2. **Match to pattern** - Which pattern above fits this insight?
3. **Generate 10+ options** - Try 3-4 different patterns
4. **Select best** - Would YOU open this? Would Sarah forward it?

---

## Preview Text Formula

Complement subject line, don't repeat it.

`[Specific claim]. [Context]. [Gap/tension]. PLUS: [bonus]`

**Example:**
- Subject: "Why 1.5 million students are in microschools now"
- Preview: "It started with frustrated parents. Then the pandemic hit. Now it's a movement. PLUS: how to find one near you."

---

## Anti-Patterns

**Don't:**
- Start with "This week in..." or "Our latest..."
- Use clickbait you can't deliver on
- Write vague promises ("Something exciting")
- Use ALL CAPS for emphasis
- Add emojis
- Stop at 2-3 options (generate 10+)
- Use hedge words ("might," "could," "possibly")
- Write generic promises ("many people" vs "1.5 million students")

---

## 10 Commandments Quick Reference

Score your top 5-7 options. Aim for 4-6 per subject line:

1. **Numbers** - Specific stats, not "many" or "several"
2. **Negativity Bias** - Potential loss, mistake, consequence
3. **Pattern Interrupt** - Challenge common belief
4. **Target Callout** - Name specific audience
5. **Problem Callout** - Identify pain point immediately
6. **Confidence** - Strong language, no hedge words
7. **Aesthetics** - Clean, scannable, under 50 chars
8. **Benefit** - Clear outcome promised
9. **Social Proof** - Authority, results, validation
10. **Warning** - Urgency or importance

**Full framework:** `references/10-commandments-checklist.md`

---

## Quality Checklist

Before finalizing:

- [ ] **Under 50 characters?** (mobile preview test)
- [ ] **4 U's pass?** (3/4 minimum: Useful, Urgent, Unique, Ultra-specific)
- [ ] **Would you remember it 5 minutes later?** (memory test)
- [ ] **Would you forward it?** (quotability test)
- [ ] **Is meaning clear even truncated?** (clarity test)

---

## Bundled Resources

| Resource | Contents |
|----------|----------|
| `references/newsletter-subject-lines-analyzed.md` | Real OpenEd examples with full scoring |
| `references/10-commandments-checklist.md` | Evaluation framework with examples |
| `references/sticky-sentence-techniques.md` | Literary devices for memorable lines |

---

## Related

- `opened-daily-newsletter-writer` - Full newsletter workflow
- `article-titles` - Blog/article titles (longer, SEO-focused)
- `segment-titles` - Segment headline writing

---

*Generate 10+ options using multiple patterns. Score with 10 Commandments. Select best.*

Overview

This skill writes high-open-rate subject lines for OpenEd Daily using 15 proven formulas plus a 10-Commandments evaluation. It generates 10+ distinct options, scores the top contenders with systematic criteria, and selects the best lines optimized for mobile previews. The goal is clear: increase opens with concise, memorable, and honest subject lines.

How this skill works

I identify the single core value or insight in the newsletter, match that insight to multiple subject-line patterns (Number + Why, Contrast, Curiosity Gap, Contrarian Truth, etc.), and produce 10+ candidate lines across 3–4 patterns. Then I score the top 5–7 options using the 10 Commandments and the 4 U's test (Useful, Urgent, Unique, Ultra-specific) and run final checks for length, clarity when truncated, and forwardability.

When to use it

  • Preparing OpenEd Daily or education-focused email editions
  • You need mobile-friendly subject lines (35–50 chars ideal)
  • When you want data-backed, repeatable subject-line generation
  • Before A/B testing newsletter subject candidates
  • When headlines must balance curiosity with clarity

Best practices

  • Start by naming the single most valuable insight; build the line around that
  • Generate at least 10 options across 3–4 different patterns
  • Prefer concrete numbers and specific claims over vague words
  • Score top candidates with the 10 Commandments and the 4 U's test
  • Keep lines clear if truncated; avoid hedging language
  • Avoid clickbait, ALL CAPS, and emojis

Example use cases

  • Daily edition highlighting one research finding: produce 10+ concise subject lines and pick the top 2 for A/B test
  • Feature story about a school innovation: craft contrast and curiosity-gap lines, score them, and select best
  • Subscriber growth campaign: create targeted subject lines naming the audience and a clear benefit
  • Special report release: use Number + Why and Social Proof patterns to increase credibility
  • Quick-breaking education policy update: emphasize urgency and the problem callout

FAQ

How many subject line options will you produce?

I generate 10+ distinct options and then shortlist the top 5–7 for scoring.

How do you pick the final subject line?

I score shortlisted lines with the 10 Commandments, apply the 4 U's test, check mobile length and clarity when truncated, and choose the line that best balances score and real-world appeal.