As the spread of age at entry when the two groups are combined is similar to that of any single school year group this is not considered to be problematic. (gov.scot)
Thus the difference in age within a typical school year group does not appear to significantly explain variations in social, emotional and behavioural development at school entry. (gov.scot)
A game for your students to play, would probably suit any Secondary School year group. (tes.com)