Readiness of the child:
Child can count in tens
Materials
- Base 10 blocks (units, tens, hundreds)
- Pen (pencil)
- Paper
Activities (Let the child do as much as possible)
- Using a 10-block, let the child quickly collect ten 1-blocks (just grab units and lay them side to the 10-block so that you would have a “copy” of the 10-block). Do as many times as possible (perhaps even collecting twenty or thirty units) to build confidence in that a string of units that is of equal length to a 10-block indeed gives ten units and that we can be sure of this without “counting.”
- Pick a number between 10 and 20; lay out that much of units; and let the child count how many there are, using the previous idea of grouping ten units into a copy of 10-block. Let the child write out the total in base 10. Explain the relation between the physical grouping into tens first with the algebraic representation in base 10.
- Do the converse of the previous activity: Start with a decimal number between 10 and 20, and represent them physically using 10-blocks and units.
- Attempt to do the three exercises above with bigger numbers between 10 and 99.