Play in a bounce house outside? I found an awesome deal on a bounce house (even goes with our theme) for DD's party. Her party is December 12th, and we live in GA. The year I had her, it was 60s, close to 70. The average is probably low to mid 50s. Would you let your DC play in one if the weather was in the 50s?
Re: What is the coldest you would let DC...
DD loves playing outside, so unless it's raining or snowing heavily, I let her play even when it's cold. I make sure to bundle her up, and bring her inside if it seems like she's getting too cold.
You might want to let the other parents know that the kids will be playing outside so they can dress them accordingly. I wouldn't want DD playing outside in a dress in the cold weather!