Binary Numbers / dichotomous sorting Set

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Use this set of cards, lid, and keys to teach binary numbers or dichotomous sorting. Long square keys represent True or 1 bits, while long cylindrical keys signify False or 0 bits. Print 32 blank cards, cut either "True" or "1" notches for T keys, or "False" or "0" notches for F keys on the upper edge of the cards. Include an example card with binary number '10100' or decimal '20'. Although you can design various cards, it is easier to print them blank and cut according to your requirements. This concept has roots in Jacquard looms, Hollerith cards, and McBee key sort system. The design can also accommodate standard index cards with a one-hole punch. To use the cards, align them with the bevel on the right side and place them in the beveled sorting lid. Slide the keys into their respective holes, ensuring correct coding. When picking up the lid, only the coded card will fall out. For instance, inserting 1,1,0,0, and 0 keys from left to right will release decimal #24 card. For teaching dichotomous or single-key sorting, assign each hole a Y/N, T/F, or other question. Answer these questions to select cards satisfying all conditions when lifting the lid. Discuss why multiple cards fall out if only '1' keys are used and how to create an OR function system. Consider the least number of Y/N questions needed to sort students in a class. Demonstrate binary sorting by using a single T key to arrange shuffled number cards in order.