The purpose of the study is to introduce Mr. Peanut test used for measuring visual-spatial dimension of the working memory capacity (WMC). Research showed that WMC is an individual difference variable that affect multimedia learning (Mayer, 2014). Although WMC research for older populations is abundant, little studies have been conducted for children. In addition, tests aiming to measure younger populations’ WMC remain insufficient (Alloway, Gathercole, & Pickering, 2006). In this study, we presented the Turkish version of the Mr. Peanut test (Case, 1985) with directions about using the test. We also referred the computerized version of the test which was developed by Millisecond Software Company (Inquisit Scripts, 2016). In the test, a clown figure (Mr. Peanut) who decorates himself with the purple stickers is presented to the participants for a short length of time. Then, he disappears and appears again with no stickers on it. The task of the respondents is to recall of the position of the stickers by showing the position of the sticker on the clown's body. Participants WMC is calculated based on the stickers that the respondent could remember. The literature showed evidence that the test is a valid and reliable measure of visual spatial dimension of WMC.