The children are at school today. Where were they yesterday?

Where were they yesterday?The children were in the park yesterday.The children were at home yesterday.The children were in the museum yesterday.The children were in the yard yesterday.The children were in the hospital yesterday.The children were in the Zoo yesterday.The children were in the kindergarten yesterday.The children were in the swimming pool yesterday.The children were in the field yesterday.The children were in the room yesterday.