a term used widely but imprecisely for cases of low attainment or for performance which is deemed to be less than anticipated should be the case in the circumstances. Identifying such expected performance is hugely questionable. The term also needs to be used carefully to take account of the socioeconomic, cultural, and personal issues which may be significant factors (see potential).
a term used for the most extremely disadvantaged social stratum.
a phenomenon, especially noted in the USA, where students opt for courses which are of lower status, challenge, or reputation than that for which they would appear to be qualified.
the idea, originating in behaviourism, that responses, functions, or associations that are practised, exercised or rehearsed will be strengthened compared to those unused.