These blocks are designed to be used to help teach kids time and fractions. These two ideas often give kids trouble and a visual learning aid can really help kids who are struggling to understand.
This study showed that hands on learning increases motivation and student performance by up to 20% compared to students usinga textbook. They also showed that students who took part in hands on learning on a weekly basis outscored their peers in math by 70% of a grade level and 40% of a grade level in science.
I designed these blocks using blender and freecad. They are much cheaper than there commercial alternative, coming in at a total of about $3.38 for a complette set.
See a commercial version here for $15