I'll race you to that green sign

I saw a family on the Parkway. The mother was pushing a stroller, and two sons were riding bikes. The older son was about 10, and he was about 100 yards in front of his family. As I neared him, I said to him, "I'll race you to that green sign" (a distance of about 100 yards). He smiled, turned around, and took off to the sign. Since this was a rest day, I just continued my pace. As I neared the sign, the boy had turned around and was heading back toward me. As I ran past him, I held out my hand and gave him a "high 5".