The 13-year-old, who cannot be named for legal reasons, appeared in private at Hamilton Sheriff Court yesterday where he faced one charge of murdering Dawn McKenzie.
He is alleged to have repeatedly stabbed her on the head and body with a knife in her home on Friday. The schoolboy made no plea or declaration and was remanded in custody to a secure children's unit. He is expected to make a further court appearance in a week's time.
Mrs McKenzie, of Hamilton, Lanarkshire, was found injured at her home shortly after 8pm on Friday but died later at Hairmyres Hospital, in East Kilbride.
She had left her senior post looking after babies and toddlers at the Glenburn House Nursery in East Kilbride in November, and, with her husband, Bryan, 36, had chosen to start caring full-time for youngsters.
A spokeswoman for the nursery said: "We are utterly devastated at the tragic loss of Dawn McKenzie, a much loved colleague and friend.
"She was a devoted practitioner for 11 years and touched the lives of so many."