1. Calculation execution errors
The student knows the rule but loses accuracy while carrying it out: signs, regrouping, fractions or arithmetic steps. Mark the exact step where errors cluster instead of only telling the student to slow down.
2. Concept errors
The formula may be memorized, but the student cannot explain why it applies or confuses similar concepts. More worksheets are less useful than verbal explanation, examples and counterexamples.
3. Condition-reading errors
The student finds numbers in a word problem but misses relationships such as “at least,” “difference,” or part-versus-whole. Separate what is given, what is asked, and how the quantities are related.
4. Solution-order errors
Individual calculations are correct, but the student does not know what to do first. Before writing equations, ask for a one- or two-sentence plan.
5. Checking and recovery errors
The answer is produced without checking units, signs or whether every condition was satisfied. Instead of merely redoing the same problem, record the cause in one line and reassess it with a similar problem later.