With this activity, students will practice factoring trinomials (where a = 1). There are 4 versions of worksheets. Each worksheet includes 15 tasks, divided into 3 groups for convenience. A student has to solve the task and paint the factors with a color that is indicated to the right of the task. Below every group of tasks there is a set of answers. This form of work is interesting for children and makes teacher’s checkup easier. It also includes an ANSWER KEY!