Impacts of number lines and circle visual displays on caregivers’ fraction understanding

•Brief picture-book interventions may improve adults’ fraction understanding.•Parents’ fraction performance benefited from both number lines and circle area models.•Caregivers were aware of their learning over time.•Caregivers may play a significant role in children’s fraction understanding. Playful fraction picture books, together with math instructional content called “back matter,” may promote fraction learning, which is crucial because fractions are difficult and often disliked content. However, open questions remain regarding how different types of back matter may affect caregivers’ ability to use fraction picture books as a teaching tool. The current study offers a novel investigation into how back matter affects caregivers’ (N = 160) fraction understanding (i.e., equivalence and arithmetic) and subjective beliefs about math using a pretest/posttest design. We contrasted existing back matter text with research-informed back matter text crossed with either circle area or number line visual displays. Caregivers’ performance improved from pretest to posttest in the Researcher-Generated + Circles condition (fraction equivalence) and in the Existing + Circles, Researcher-Generated + Circles, and Researcher-Generated + Number Lines conditions (fraction arithmetic). In addition, caregivers were aware of their learning; they predicted improvements in their fraction arithmetic performance over time. These findings suggest that brief interventions, such as back matter in children’s picture books, may improve adults’ fraction understanding.