Photo by Tzvi Meller As much as it seems counter-intuitive, teaching new vocabulary in semantic sets (e.g. jobs: doctor, teacher, lawyer etc. or colours: red, blue, yellow etc.) does not facilitate learning. As far back as in the 1990s, research showed that teaching semantically related items is counter-productive . Have these findings been taken on board? Of course not! New vocabulary in elementary level coursebooks is routinely presented in lists of semantically related items. Semantic sets and interference In 1993, Thomas Tinkham investigated the effect of learning new words under two conditions. One group received a list of words belonging to the same semantic set while the other was given random, semantically unrelated words. Tinkham revealed that list-learning of unrelated words yielded better results as the second group performed significantly better when they were asked to recalled the target words. A few years later, Rob Waring (1997) replicated the experiment with two gr...