I'm a December kid. Socially never bothered me at all having a later birthday than my peers. Academically, I was never behind, I was average in the lower grades and by grade 8 was at the top of my class. It all depends on your kid. If they are socially and behaviourally ready, I would send them. My daughter is a November baby and we sent her to JK. She is a little behind, but that wouldn't have made me send her the year later, she is in grade 2 now and only behind in reading, all other aspects she is average. Next year she will be all caught up in every subject.