Browsing the Kit Cosmetics site I found these three gorgeous polishes, released as the Chalk It Up range:
Chalk It Up is a very appropriate name, the colours do look just like the colours of my kids' pavement chalks. Left to right they are: Game On (pastel melon), High Roller (pastel mint) and Winner Takes (pastel pink).
I'm definitely coveting all three of these. They are AU$15.95 each from Kit, and annoyingly High Roller is out of stock.