Order of Operations Online (OoOO???)

FIRST PERIOD: I want your feedback on these!! Which are the right level of difficulty? Which are more fun than the others? Which cover the right types of problems (especially exponents or fractions)? ​Tell me in person or leave a comment! Be sure to make it clear which one you're talking about!

1. Exploring the Order of Operations (you click on operations in order they should be done; computer does them. Too easy?)
2. Order of Operations Royal Rescue Game 
3. Order of Operations Millionaire Game (includes ads; for 1 or 2 players. Mute your volume!)
4. Order of Operations Arithmetic Quiz (important: click to turn on all operations (+, -, etc.) and "Triplet"; for a challenge, try Negative too)
5. Math Playground Order of Operations Game  
6. Click which operation to do first (the basics... might help you catch up if you need it)
7. XPMath Order of Operations (let me know how this one goes!)