Because the Production test considers proportion of information units provided per word, higher post-test scores might be the result of children producing more information units about the same words that they knew at pre-test (i.e., the intervention led them to deepen their knowledge of those words that they already knew), or they might be the result of children producing information units for more of the words (i.e., the intervention led them to learn new words). To investigate these alternatives, weconductedaseriesofpairedt-testsonchildren’spre-andpost-testscoresfortheindividualTargetwordsthatwereincluded ontheProductiontest,usingBonferronicorrectionsformultiplecomparisons.Thesetestsrevealedthatchildrenproducedmore information units per word at post-test for 7 of the 8 Target words in the Realistic theme that were included on the Production test and for 12 of the 13 Target words in the Fantastical theme that were included on the Production test. This indicates that, even if children already knew some of the Target words at pre-test, they gained more information about these words as a result of our intervention.