concept videos

These concept videos were produced as part of our Bakersfield City School District ABACUS Monthly series.

Comparison Symbols

Educators hold an armory of devices to recall which symbols mean "less than" or "Greater than"...but why were those symbols chosen, and what role does the number line play?

Multiplying and Dividing Fractions and Decimals

Decomposing fractions and decimals allow for the area model to take hold when exploring multiplication and division beyond whole numbers.

Alternative Division

Long division is regarded by many as the point in their math learning when they stopped loving the subject.  In reality, a partial sum approach can be more efficient and grounded in friendly multiples.

Euclid is My Homeboy

What if you could find greatest common factor using only subtraction?  Euclid had you covered 2,400 years ago.

Open Number Lines

When students build their own visuals, everyone wins.  An open number line allows deeper concepts, such as flexible place values and difference as the distance between two points, to take hold.

Fractions and Polygons: Perfect Together

Any regular polygon can be easily broken into equal-sized why aren't we using this when we introduce fractions? See how!

Egg Carton Fractions

The egg carton, with its 12 compartments, can be turned into a handy manipulative in exploring concepts of fractions.

Foldable Number Line

Any post-it note or index card can become a number line, and a paper clip can become the vehicle to explore.
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