What are cool inventions to come up with for high school projects

1. Solar-powered backpack with built-in phone charger

2. Automatic plant watering system
3. Smart doorbell with facial recognition
4. DIY fitness tracker
5. Portable solar cooker
6. Bluetooth-enabled smart mirror
7. Automated pet feeder with timer and portion control
8. Voice-controlled home automation system
9. Self-watering herb garden
10. Wearable tech device to monitor and manage stress levels.