When did your baby start going to school?

I sent 3 weeks ago when she was 2+m. She is developing runny nose and cough, may have picked up outside of IFC as we have visits with relatives. She started sleeping better since she started, initially it was sleeping earlier and waking later with 1 feed. She is now sleeping at around 830pm to 930pm and waking at 7am without any night feed. IFC is able to engage her better than at home!