Introduction

1. Rosa Elena Arroyo-Carmona1, Adriana Martínez González1, Enrique González-Vergara2, Aarón Pérez-Benítez1* 1 Facultad de Ciencias Químicas. Benemérita Universidad Autónoma de Puebla. 14 sur y av. San Claudio. Col. San Manuel. C. P. 72570, Puebla, Pue. MÉXICO, 2Centro de Química-ICUAP. E-mail: <aaron.perez@correo.buap.mx> Building paper flowers for teaching-learning descent in symmetry C6v Introduction Symmetry is around us, everywhere…, anytime; always captivating our attention. We can find it in nature in animals, in flowers, etc. (Figure 1). Figure 1 Symmetry in nature and manmade things Everybody likes symmetry: artists, scientists and common persons; thus, it is not amassing that many manmade things, real or imaginary, are symmetric: architectonical buildings and airplanes are examples of the first class and pictures and palindromes (Figure 2) are examples of the second one. • Starting materials are: Two paper sheets of different color, scissors, glue stick and pipe cleaners (Figure 3a). • Fold up paper sheets in quarts and copy the pattern in figure 3b. • Cut out the templates and fold them as dickey bows (Figure 3c). • Bend a pipe cleaner as a waking stick and use it for joining three dickeys placed side by side (Figure 3d). • The pipe cleaner must be twisting by down and the petals have to be extended pressing them close to their centers with thumb and index finger. • Use one or two color dickeys for building flowers belonging to symmetry point groups C6v, C3v, C2v, Csand C1.Their positions in figures 3e-i must be kept). • In our example, a two color dickey was made gluing a white half dickey over an orange pattern. • Conclusion • The construction of these ornaments in science popularization workshops really like to children (and their moms ) as we corroborated in several occasions. Preliminary data indicate children‘s predilection by symmetry point group C3v instead of C6v as we thought initially; however the reason is probably the color alternation. Paper flowers for teaching Cnv-symmetry descending in a science popularization workshop for children Figure 2 Linear and square palindromes (A palindrome is a string that reads the same forward and backward). a b c As in all matters in which the spatial visualization is required, a physical 3D-model is a very useful tool for its teaching-learning process and symmetry is not the exception. That is why we carry out science popularization workshops, in which children make flowers with 4, 6 and 8 petals (symmetry point groups C4v, C6v, C8v ), starting from a sheet and pipe cleaners. Here is presented the procedure for making six petal flowers, in which their petals are systematically changed in color to succeed in making flowers belong to C6vand its subgroups C3v, C2v, Csand C1. d e f g h i Figure 3 Procedure for making paper flowers belong to C6v(e), C3v(f), C2v(g), Cs(h)and C1(a), being chiral the last one.