Maybe your child isn’t deliberately lazy. He might just be defective. Keeping in mind that a healthy child takes 8 years to complete 8 school grades, you can use this handy guide to see how long it might take your child to finish school, depending on what kind of defect your child has:

Defective vision: 8 years
Defective teeth: 8.5 years
Defective breathing: 8.6 years
Hypertrophied tonsils: 8.7 years
Adenoids: 9.1 years
Enlarged glands: 9.2 years

Woe is the child with enlarged glands and defective teeth. Luckily, these defects can all be counteracted with proper nutrition. This scientific study is based on a sample size of 27 children.

WHY SOME CHILDREN ARE ALWAYS LAZY: Experts Have Made a Study of This Familiar Weakness in Childhood and Suggest a Cure (PDF)

From July 24, 1910