Hi sh22,
It is not unusual for a child with learning disabilities to show weaknesses in rote activities such as math facts, naming objects/letters/colors, naming months of the years and or spelling. These difficulties are often red flags for dyslexia (reading disabilities) among other issues. And, these same children can be brilliant at math concepts, reading/listening comprehension and other abstract thinking skills.
Is your child 2-E? It would take more than a few WJ achievement tests to determine this - generally there would be cognitive and psychological testing along with additional achievement testing.
Does your child have LD? Again - these few subtests and your brief description cannot diagnose an LD. But, if you have concerns, I urge you to get a full evaluation. A parent's intuition is often on the mark.
