Data was collected via a 13-inch PC laptop using PsycoPy2 Version 1.85.4 The program may require adjustments to successfully run in a different version of PsychoPy or a different screen size **Component Contents:** The file: "RLAD_Jan11.py" is the PsychoPy program that is used to control and present the stimuli The "Stimuli" folder contains all the jpgs that the .py program pulls and displays The three excel files ("RL-AD_StimList_Disc.xlsx", "RL-AD_StimList_SquareCont.xlsx", "RL-AD_StimList_Numeral.xlsx") contain the information about each trial to tell the .py program which stim to present on a given trial The README file is not necessary to run the program and contains all of this information, so that if you download all the contents these instructions remain. **To run the study:** you need all of the above files/folders as is - meaning, the names of the stim lists, the name of the stimuli folder, and the name of each stimulus are built into parts of the program and so changing the names will change the paths (but of course, you can go in and change the path if you need). The files/folders can be put anywhere, as long as their relative locations stay as is - so, the Stim Lists and .py program need to be in the same folder and the stimuli are in a sub-folder called "Stimuli". The program needs to be opened through coder-view of PsychPy. Once it's open press the little green circle with the running human inside to begin. A pop-up window should open asking for: 1 Participant ID: will not impact the program administration, but will be outputted in the datafile for your own tracking 2 Age: will not impact the program administration, but will be outputted in the datafile for your own tracking 3 Testing Location: will not impact the program administration, but will be outputted in the datafile for your own tracking. Note that because this will be saved in the raw data files, to make anonymous data sharing easier later, it's likely you do not want to record specific locations here (e.g., XX NAME MONTESSORI SCHOOL), but instead more general information (e.g., "school", "lab"), or not to record anything at all. But of course, that's up to you and your IRB. 4 Experimenter Initials: will not impact the program administration, but will be outputted in the datafile for your own tracking. 5 Visual Condition: THIS IS NECESSARY FOR THE PROGRAM TO RUN. you have three options: "DS", "SqCS", or "NM" (all case sensititve). DS will display the discrete set of dots stimuli (associated with the Disc stim list) SqCS will display the squares with area matched to the disc stimuli (associated with the SquareCont stim list) NM displays the numeral stimuli matched to the number of the discrete stim (associated with the Numeral stim list). Note that for NM, we also said the number words aloud to the children while pointing at the numeral, to not rely on children's numeral ID alone. Once the information is entered (at a minimum, 5 Visual Condition, the rest can be blank) press OK The program should begin. To advance to another trial, press the right or left arrow key, depending on which response you'd like to select. The computer will record the key presses and output a .csv file with the trial order (because they are presented in a random order) and the response on each trial.