Seria-Think Mental Rotation Test (STI-MR)

The STI-MR is a DA measure composed of three phases: Pre-Teaching, Teaching, and Post-Teaching. The child is presented with the Original Block and the Transfer Block of the STI placed side by side. The examiner places colored buttons in 2, 3, or 4 holes and asks the child to place the same-colored buttons in the appropriate holes of the Transfer block after it has been rotated 90°, 180°, and 270°.

The teaching phase is conducted using pre-teaching items. First, the child is asked to insert colored buttons in the transfer block after rotation. Before inserting, the child is asked to visualize the correct location on the rotated block. The examiner then focuses the child on clues that help locate the correct hole — the red tape at the bottom of the block, the serial position of the button on the specific row, and the relative position of the buttons across the array.

Cronbach-alpha reliability on a sample of Grade 3 children (n = 86) was .89 for pre-teaching and .87 for post-teaching. Children in an experimental group showed significantly higher pre- to post-teaching improvement on STI-MR problems (near-transfer) and on geometry and volume perception tests than children in a control group who practiced without mediation.