In this Punnett Square practice, students use a traits chart to determine genotypes and phenotypes, and perform genetic crosses using punnett squares. The practice involves the genes and cross between two parent dogs - Rufus and Fluffy, which is fun and silly for students. The practice is scaffholded - students begin with determining basic alleles, genotypes and phenotypes and labeling these as homozygous and heterozygous. The practice also includes a a vocabulary cube of important genetics words for students to better understand the practice: genotype, phenotype, homozygous, heterozygous, dominant and recessive. Students move on to cross genes by setting up punnett squares in order to determine probabilities of genotypes and phenotypes appearing in offspring. The practice is engaging and aligned to 7th-grade science essential standards. The practice can be done as a whole class, partner or group practice or assigned as homework. It can be used as a formative assessment to assess student knowledge of using punnett squares to determine probabilities of offspring, which is heavily tested on the 7th-grade science common assessments.