While not a 'side quest' in the traditional sense, collecting coins and aiming for a high score are significant optional activities in Super Mario Land that add to its replay value. Coins are scattered throughout every stage, found in '?' blocks, hidden blocks, and sometimes dropped by defeated enemies. Collecting 100 coins will instantly grant Mario an extra life, making coin collection a vital strategy for survival.

Tips for Coin Collection:
- Hit every block: Many blocks, even seemingly empty ones, can contain coins. Make it a habit to jump and hit every block you encounter.
- Explore hidden areas: Pipes leading to bonus rooms often contain a large number of coins.
- Use Superballs: The Superball Flower allows Mario to shoot Superballs that can collect coins through blocks, reaching otherwise inaccessible coins.
- Defeat enemies: Some enemies, when defeated, will drop coins.
High Scores:
Your score is displayed at the top of the screen. Points are awarded for:
- Collecting coins.
- Defeating enemies (stomping, Superballs, Starman).
- Breaking blocks.
- Reaching the top of the flagpole at the end of a stage.
- Remaining time on the clock at the end of a stage.
Aiming for a high score encourages more aggressive play, seeking out every enemy and coin. While there are no in-game leaderboards, achieving a high score is a personal challenge and a testament to your mastery of the game. Replaying stages to optimize your coin collection and score can be a fun way to extend your playtime.