32 



Indiana University Studies 



The approximation is closest for Cleveland, but even in this 

 case the difference is large enough to make close comparisons 

 misleading. 



The Progress of Children in the Systems Studied. The 



per cent of retardation (overage) and acceleration (under- 



Retardation 



Grades 10 20 30 40 50 60 



Acceleration 

 '0 80 90 100 



II 



III 



IV 



VI 



VII 



VIII 



IX 



XI 



XII 



Av 



Fig. 6. Showing retardation and acceleration of boys (npper) and 

 girls (lower) in systems having- semiannual promotion. 



