Solve the unanswered problems using the same pattern as the student. What misconeption(s) does the student have about place value?
Adds all digits together for three digit problems. (11, 84, 16)
Adds like multiplication. (134, 131)
Adds left to right and carries to right. (789, 1112)
Subtracts lower digit from higher digit in each place value. Most common error. (126, 255)
Always regroups from tens. (265, 2112)
Reuses previous carries. (5528, 3970)
Add carry before multiplying. (500, 127)
How many times does smaller digit go into larger digit? (213, 142)
Brings down two digits instead of one. (32 r.2, 78 r.2
Writes answer below digits. (108, 1117)
Anything subtract zero is zero. (104, 530)
Regroups from hundreds if two regroupings are needed. (264, 187)
Regroups like base 10, not based on correct units. (3 yards and 2 feet, 1 quart and 3 cups)
Always regroups highest place value, regroups from right, and 0 - N = 0. (153, 110)
Left most times left most. Middle times middle. Last times last. (1243, 2081)
Ignores carries. (95, 82)
Brings down two digits instead of one. Tacks on zero for place value. (830, 520 r. 4)
Writes quotient right to left (52, 68)