According to French-language journal Archives De Pediatrie, children's attention spans vary with the time of day, day of the week and even with the season of the year.
The Institut de Medecine Aerospatiale du Service de Sante des Armees studied the attention spans of 10,000 Parisian children between ages 8 and 10. They found that the period with the lowest attention span is between 8 a.m. and 9:30 a.m. The highest levels are between 4 p.m. and 4:30 p.m.
Children show short attention spans on Sunday afternoons, but good attention spans on Monday. And they are always lower during summer than during any other season.