Presentation: in small groups (playing in pairs)

Material: strips of Bristol cardboard 2X12cm – coloured plastic plate with a diameter of 20cm – marbles – double scotch.

Create 4-5 strips of paper (cutting them out of cardboard) and draw a symbol on them corresponding to the tags proposed by the teacher (eg. a black ball, two black balls, three black balls …). Then the children stick the strips on the plastic plate with the double tape,  placing them as bridges and put a marble on the plate.

Children play the game in couples in front of a series of cards (a pack for each symbol / quantity) reproducing the symbols on the bridges that are arranged in an order (code). The child must pass the marble under the various bridges following the order of quantity indicated on the bridge strips. When a child fails to pass the marble, he/she takes the card from the pack.

The same game can be done with colours: both bridges and cards for the code sequence.