An activity device is provided that comprises a sorting substrate including multiple cavities, multiple toy blocks shaped and sized for insertion into respective ones of the cavities, and detection circuitry. The detection circuitry includes multiple sensors disposed on the sidewall of each toy block, including a first sensor disposed adjacent to the distal end of the toy block and a second sensor disposed proximally relative to the first sensor. The detection circuitry also includes at least one activator disposed on a side wall of each cavity and configured to (i) activate the first sensor of the corresponding toy block as the toy block is being inserted into the cavity to produce a first stimulus from the toy block and (ii) activate the second sensor of the corresponding toy block when the toy block is seated within the cavity to produce a second stimulus from the toy block.