Of Blocks and Base Ten

As we wrote in the previous post, we are teaching at four locations in Portland, Oregon.  One of those locations is near the junction of I-84 and I-205; that is the location whose teachers are focusing on science activities based on appropriate technology.  Hopefully, within the next few weeks the teachers at that location will be writing blog posts describing their activities.

There is a also a team which is visiting a gathering place in North Portland, near Columbia Boulevard about a mile and a half west of I-5.  At this location we are focusing on basic arithmetic.  Last night, after a timed drill in multiple-digit adding, we began to explain place value in the base ten number system.  Shawn Perez, who serves both as a teacher and a writer with our project, introduced base ten concepts using a pack of base ten blocks:

Once the kids got the basic idea of building tens, hundreds and thousands out of smaller units, we showed them how to break multiple-digit numbers down into units of thousands, hundreds and tens. Pictured at the top of this post is a student of ours named Ja Marrion demonstrating his grasp of the concept while his father (not shown) watches him.  As can be seen from these pictures, we believe in the effectiveness of manipulatives as an aid in introducing mathematical concepts.  However, we do not stop there (just as a person learning to ride a bike doesn't use training wheels forever), but insist on taking kids to the demonstration of advanced understanding and abstraction which is essential for progressing to higher order mathematics.  By this insistence we seek to correct a serious deficiency of many of the practitioners of Common Core math instruction, who leave their students dependent on manipulatives and unable to take that necessary next step of abstraction.

Another very encouraging thing happened last night, namely, that a couple of adult residents of the neighborhood volunteered their services to help us in our efforts at the North Portland location.  One of them can start helping us immediately, and the other will be available after the beginning of next year.