vantages.
In the examination his intelligence is very even as far as it
goes, but stops rather abruptly after the 10-year tests. Will
unquestionably pass as normal among unskilled laborers, but his
intelligence will never exceed the 12-year level and he is not
likely to advance beyond the seventh grade, if as far.

[Illustration: FIG. 12. BALL AND FIELD. R. G., AGE 13-5, MENTAL
AGE 10-6]

_F. D. Boy, tested at age 10-2; I Q 83, and again at 14-1;
I Q 79._ Mental age in the first test was 8-6 and in the second
test 11. Son of a barber. Father dead; mother capable; makes a
good home, and cares for her children well. At 10 was doing
unsatisfactory work in the fourth grade, and at 12
unsatisfactory work in low sixth. Good-looking, normal in
appearance and social development, and though occasionally
obstinate is usually steady. Any one unacquainted with his poor
school work and low I Q would consider him perfectly normal. No
physical or moral handicaps of any kind that could possibly
account for his retardation. Is simply dull. Needs purely a
vocational training, but may be able to complete the eighth
grade with low marks by the age of 16 or 17.

_G. G. Girl, age 12-4; mental age 10-10; I Q 82._ From average
home. Excellent educational advantages and no physical
handicaps. At 12 years was doing very poor work in fifth grade.
Appearance, play life, and attitude toward other children
normal. Simply dull. Will probably never go beyond the 12- or
13-year level and is not likely to get as far as the high
school.

Those testing 80 and 90 will usually be able to reach the eighth grade,
but ordinarily only after from one to three or four failures. They are
so very numerous (about 15 per cent of the school enrollment) that it is
doubtful whether we can expect soon to have special classes enough to
accommodate all. The most feasible solution is a differentiated course
of study with parallel classes in which every child will be allowed to
make the best progress of which he is capable, without incurring the
risk of failure and non-promotion. The so-called Mannheim system, or
something similar to it, is what we need.

AVERAGE INTELLIGENCE (I Q 90 TO 110). It is often said that the schools
are made for the average child, but that "the average child does not
exist." He does exist, and in very large numbers. About 60 per ce