In this genetics punnett square practice, students use a traits chart to determine genotypes and phenotypes, and perform genetic crosses using punnett squares. Students cross genes by setting up punnett squares in order to determine probabilities of genotypes and phenotypes appearing in offspring. On the third page, the process is reversed - teachers should write the crosses of the offspring, and students will determine the original genotypes of the parents. The practice is 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.