Miraculous Ladybug/Headscratchers

Season 1

 * In The Bubbler, Nino sees a small kid being taken being for chores when he goes to the park. I don't know if I'm spoiled or just got lucky with my own mother, but that kid looks way too young to be doing chores.


 * In Mr. Pigeon, Ladybug's Lucky Charm is a coin. She ends up saving the day by buying a bag of popcorn from a vending machine. At the end of the battle, she throws up the coin for she can turn everything back to normal. My problem is how she got the coin back? We never see her retrieving it but she still has it just in time to world heal. Did it fall out the part of the vending machine that spits out spare change? If so, how? Since it's a magic coin, does it just have infinite amount of money and would've fallen in there to begin with?
 * Another is: what part did Alya have in the project? The assignment seems to be a partner one, yet we only see Marinette working on the derby hat and the show only credits it as her hat. Why present the assignment as a partnership at all if only one person is going to be credited as the winner?
 * Also Nino is with Adrien when they present the hats. Why? Was the class already paired up and when they presented the assignment to class including the part Adrien would be modeling the winning and since Nino was already paired with Adrien, he got exempted from the assignment as well?