Kindergarten (79 different terms out of the 1,000 were used on this level - average 25 terms per book)(Average age - 5 years old)
First grade (128 different terms out of the 1,000 were used on this level - average 49 terms per book)(Average age - 6 years old)
Second grade (185 different terms out of the 1,000 were used on this level - average 66 terms per book)(Average age - 7 years old)
Third grade (269 different terms out of the 1,000 were used on this level - average 96 terms per book)(Average age - 8 years old)
Fourth grade (345 different terms out of the 1,000 were used on this level - average 132 terms per book)(Average age - 9 years old)
Fifth grade (402 different terms out of the 1,000 were used on this level - average 161 terms per book)(Average age - 10 years old)
Sixth grade (437 different terms out of the 1,000 were used on this level - average 180 terms per book)(Average age - 11 years old)
Seventh grade (514 different terms out of the 1,000 were used on this level - average 208 terms per book)(Average age - 12 years old)
Eighth grade (590 different terms out of the 1,000 were used on this level - average 212 terms per book)(Average age - 13 years old)
Ninth grade (455 different terms out of the 1,000 were used on this level - average 183 terms per book)(Average age - 14 years old)
Tenth grade (431 different terms out of the 1,000 were used on this level - average 201 terms per book)(Average age - 15 years old)
Eleventh grade (469 different terms out of the 1,000 were used on this level - average 217 terms per book)(Average age - 16 years old)
K-12math.info examines mathematics textbook series to determine where and how 1,000 conceptual, operational and notational terms are used. The information is displayed in a spreadsheet format. The information contained within this Web site is solely that of its founder - Jim Kelly.