Assessment Overview
This rubric evaluates both the technical correctness of your block construction and your understanding of the economic principles underlying blockchain block production. Teams are assessed on their ability to optimize fee collection, follow constraints, and communicate their strategy.
1. Valid Block Construction
15 Points
Block meets all technical requirements and constraints.
Excellent
15 pts
Block size exactly at or efficiently below 10 units. All transaction IDs valid (tx_001-tx_020).
No mathematical errors in size calculation.
Good
12 pts
Block size within constraint (≤10 units) but not optimally filled. All transactions valid.
Minor calculation checked and corrected.
Fair
8 pts
Block size within constraint but significant unused space. One invalid transaction ID or
calculation error caught during verification.
Poor
0-5 pts
Block exceeds 10 unit constraint, multiple invalid transactions, or fundamental
misunderstanding of requirements.
2. Fee Optimization Strategy
15 Points
Effectiveness of transaction selection to maximize total fee collection.
Top 3 Teams
15 pts
Achieved one of the three highest total fee amounts in the class. Demonstrates optimal or
near-optimal transaction selection.
Top 50%
12 pts
Total fees in upper half of all teams. Good strategy with room for optimization. Considered
fee-per-unit ratios.
Below Average
8 pts
Total fees below class median. Strategy shows basic understanding but missed key optimization
opportunities.
Bottom 25%
0-5 pts
Total fees in bottom quartile. Poor transaction selection (e.g., many low-fee or oversized
transactions included).
3. Hash Calculation
10 Points
Correct application of simplified hash formula.
Correct
10 pts
Hash correctly calculated: sum of last digits from all selected TX IDs. Work shown clearly.
Minor Error
7 pts
Hash calculation has minor arithmetic error but method is correct. Or work not clearly shown.
Method Error
4 pts
Misunderstood hash formula (e.g., used full TX numbers instead of last digit) but attempted
calculation.
Missing
0 pts
Hash not calculated or completely incorrect with no valid work shown.
4. Peer Verification & Accuracy
5 Points
Block verified by another team; all calculations accurate.
Complete
5 pts
Peer verification completed and signed. All calculations verified as correct by peers.
Partial
3 pts
Verification completed but peers found minor errors that were corrected.
Incomplete
0-1 pts
No peer verification obtained, or major errors not corrected after verification.
5. Presentation & Strategy Explanation
5 Points
Clear communication of approach, trade-offs, and understanding of concepts.
Excellent
5 pts
Clear, confident presentation. Explains strategy using economic terms (fee density, opportunity
cost). Discusses specific trade-offs made.
Good
4 pts
Adequate presentation. Explains basic strategy. Some discussion of trade-offs but lacks depth
or economic terminology.
Fair
3 pts
Basic presentation. Describes what was done but limited explanation of why. Minimal trade-off
discussion.
Poor
0-2 pts
Unclear or incomplete presentation. Cannot explain strategy. No understanding of trade-offs
evident.
Grading Summary Table
| Criterion | Max Points | Points Earned |
|---|---|---|
| 1. Valid Block Construction | 15 | |
| 2. Fee Optimization Strategy | 15 | |
| 3. Hash Calculation | 10 | |
| 4. Peer Verification & Accuracy | 5 | |
| 5. Presentation & Strategy Explanation | 5 | |
| TOTAL | 50 |
Grade Scale
| A (45-50 pts) | Excellent optimization, correct calculations, clear understanding |
| B (40-44 pts) | Good strategy, minor errors, solid understanding |
| C (35-39 pts) | Adequate work, some optimization missed, basic understanding |
| D (30-34 pts) | Below average optimization, multiple errors, limited understanding |
| F (0-29 pts) | Poor optimization, major errors, or incomplete work |
Grading Notes for Instructors
- Fee Optimization Ranking: Calculate all teams' total fees and rank them. Award points based on relative performance to encourage competition.
- Invalid Blocks: If a team's block exceeds 10 units, they cannot win fee optimization points (max 12 for criterion 2) even if fees are high.
- Partial Credit: Award partial credit liberally for criterion 1 if teams show clear effort but made calculation mistakes that were later corrected.
- Presentation: Focus on understanding of trade-offs and economic reasoning, not presentation polish.
- Class Discussion: After presentations, reveal the optimal solution and discuss why it works. Use this as a teaching moment about the knapsack problem and real-world validator incentives.
Learning Outcomes Assessment
This assignment assesses students' ability to:
- Apply economic optimization principles (fee maximization) under constraints
- Understand blockchain block structure and space limitations
- Recognize validator/miner incentive mechanisms
- Work collaboratively to solve complex resource allocation problems
- Communicate technical strategies using appropriate terminology
Connection to Course Goals: This hands-on activity reinforces concepts from lectures on blockchain economics, transaction fee markets, and the economic incentives that secure decentralized networks.
© Joerg Osterrieder 2025-2026. All rights reserved.