Big ideas, sometimes referred to as key, core, fundamental or threshold concepts, are widely applicable concepts at the heart of disciplines that are or have been central and influential for their fields. Attention here is particularly directed to meta-concepts common to sister disciplines in the sciences. "Learning thresholds",…

Learning emphasizing fractions as a part-whole concept causes several limitations in developing fraction knowledge and inhibits proportional reasoning. We use fractions as quotients as the first context introduced in our learning trajectory. We report the teaching experiment results using the improved learning trajectory on thirty 4th grade…

Learning the content of entrepreneurship arithmetic is an extension of social arithmetic that focuses on mathematical calculations in business or creative economy. Most teachers do not link students' daily activities to classroom teaching and learning on traditional markets around the environment. This significantly affects the interest in…