❓ Frequently Asked Questions
Everything you need to know about ChessLocker and the ELO rating system
📊 ELO Rating System
The ELO rating system is a method for calculating the relative skill levels of players in two-player games such as chess. Named after its creator Arpad Elo, it's used worldwide in chess and many other competitive activities.
In ChessLocker:
• New students start at 800 ELO
• Ratings change after each game based on the result and the rating difference
• We use a K-factor of 32, standard for scholastic chess
• Higher ratings indicate stronger players
In a draw, both players' ELO ratings still change slightly because the ELO system is based on expected vs actual performance.
How it works:
1. Expected Score: Based on rating difference, the system calculates what "should" happen
• Higher-rated player is expected to score more than 0.5 (closer to winning)
• Lower-rated player is expected to score less than 0.5
2. Actual Score: In a draw, both players get 0.5 points
3. Adjustment: The difference between expected and actual determines the rating change
Example: If a 1000 ELO player draws with an 800 ELO player, the 1000 player loses points because they were expected to win, while the 800 player gains points for holding a stronger opponent to a draw.
Why This Makes Sense:
• Upsets are rewarded: A weaker player holding a stronger player to a draw deserves rating points
• Underperformance is penalized: A stronger player failing to beat a weaker opponent loses rating points
• Accurate rating reflection: This helps ratings converge toward true playing strength
The ELO formula uses these components:
New Rating = Old Rating + K × (Actual Score - Expected Score)
Where:
• K = 32 (K-factor for scholastic chess)
• Actual Score = 1 for win, 0.5 for draw, 0 for loss
• Expected Score = 1 / (1 + 10^((OpponentRating - YourRating)/400))
Example Calculation:
Player A (1000 ELO) beats Player B (900 ELO):
• Expected score for A: 1 / (1 + 10^((900-1000)/400)) = 0.64
• Actual score for A: 1 (win)
• Rating change for A: 32 × (1 - 0.64) = +12 points
• New rating for A: 1000 + 12 = 1012
Teachers can manually adjust student ELO ratings outside of regular games for various reasons:
• Academic Performance: Quiz results, homework completion
• Skill Development: Puzzle solving, tactical training, opening study
• Behavioral Recognition: Positive reinforcement or corrections
• Special Achievements: Tournament participation, exceptional performance
Best Practices:
• Use small adjustments (+1 to +5) for daily activities
• Reserve large adjustments for exceptional circumstances
• Monitor class ELO economy to prevent inflation
• Document reasons for accountability
💡 General Usage
1. Navigate to your class page
2. Click "Add Student" button
3. Fill in student information (name, grade, optional email)
4. Student starts with 800 ELO rating
5. Optional: Set a password for student to access their own dashboard
1. Go to your class page and click "Record Game"
2. Select the white player from the dropdown
3. Select the black player from the dropdown
4. Choose the result (White Wins, Black Wins, or Draw)
5. The ELO preview will show expected rating changes
6. Click "Record Game" to save and update ratings
Tip: You can add optional notes about the game for future reference.
Active Students:
• Appear in game recording dropdowns
• Shown on leaderboards
• Can participate in tournaments
• Count toward class statistics
Inactive Students:
• Hidden from most views
• Game history preserved
• Can be reactivated anytime
• Useful for students who leave or take breaks
Yes! Students can have their own login to access:
• Personal dashboard with their current rating and stats
• Complete game history
• Class leaderboard (their position highlighted)
• Recent performance trends
To enable student access, set a password when creating or editing the student profile.
🎯 Tips & Best Practices
For Teachers:
• Regular Recording: Record games immediately after they're played for accuracy
• Use Notes: Add game notes about interesting tactics or teaching moments
• Monitor ELO Economy: Check the ELO Management page weekly to prevent rating inflation
• Tournament Frequency: Run mini-tournaments regularly to maintain engagement
• Manual Adjustments: Use sparingly and consistently across all students
For Students:
• Focus on Improvement: ELO is a tool to track progress, not the only measure of success
• Learn from Losses: Losses against stronger players are learning opportunities
• Challenge Yourself: Playing stronger opponents helps you improve faster
• Track Patterns: Use your game history to identify strengths and weaknesses
🏆 Tournaments
ChessLocker uses the Swiss system for tournaments, which ensures fair pairings throughout:
1. Round 1: Players are paired randomly or by ELO rating
2. Subsequent Rounds: Players with similar tournament scores are paired together
• Winners face other winners
• Players with draws face others with similar records
• Lower-scoring players get more winnable matchups
3. Benefits:
• Every player gets meaningful games throughout
• Strong players face appropriate competition
• Weaker players aren't eliminated early
• Final standings reflect consistent performance
Tournament scoring follows standard chess tournament rules:
• Win: 1 point
• Draw: 0.5 points
• Loss: 0 points
Players are ranked by total points, with tiebreakers applied when necessary.