Psychoeducational . Testing can diagnose learning disabilities. Find a psychologist who does said testing. It is worth the time and money.
Go Comprehensive . Consider having a pediatric clinical neuropsychologist 2do a comprehensive assessment of individual's a) current levels of functioning in realms of perception, problem solving, language, memory, etc; (b) behavioral, social-emotional functioning; & (c) academic skills. The assessment will help identify specific problems interfering w/learning & provide remedial strategies &/or problem work-arounds.
Psychological testin. Ld is properly diagnosed using psychological testing which can point to the specific problem and suggest appropriate treatment.
A Specific Learning. Disability = "an unexpected problem in learning in a child with an average to above-average iq" of 90 or >, defined by standardized tests of verbal, non-verbal & full-scale iq + achievement in reading decoding & comprehension, math calculations & applications & written expression, test of memory, auditory & visual processing, & executive functions & other brain functions help elucidate the causes.