CTET Class I to V 23 Dec 2021 Paper

A teacher of class V gives lots of sentences using words like 'good' 'beautiful' 'bad' 'colourful' 'old' 'young' and when learners have noticed these words which she named them as 'describing words'. Later she gives more sentences in which the learners are asked to supply these describing words. At the end she draws the attention of learners that these words are known as 'adjectives'. What is this strategy known as?