What are the key indicators that a student might have a reading disability, and how do you respond to those signs?

Some of the key indicators that a student might have a reading disability is when they do not have the consistency of word attack skills and/or when a student recognizes and/or reads a word - but does not recognize it or remember it again in a short passage. Another sign that often is a red flag is when a student cannot differentiate between sounds they hear (i.e. rhyming) or cannot hear the difference between /a/ or /e/.
One of the things that I often try with student in intervention that cannot hear the difference between /a/ or /e/ is to try another 'test' with them. I will utilize a xylophone or piano and see if they can differentiate between various pitches played. I will also have them write/encode a short vowel word with a or e in it to see if they can produce words in writing accurately.