Saturday, 19 March 2011

Abacus Addition

Today, Emily solved some simple addition problems on the abacus and using the part-whole circle concept. For example, if Mimi caught 6 fish in the morning and 3 fish in the afternoon, how many fish did she catch that day? I made worksheets for Emily based on the material covered in today's RSM lesson and asked Emily to use her tally sticks, abacus and finally, the part-whole circles to solve the problem.

We even managed what appeared to me to be a simple subtraction question using the abacus - Peter had 5 books and he returned 4 books. How many books does Peter have now?

The only problem we could not solve was a "missing start" problem - Matt took 2 more crackers. Now he has 5.  How many did he have to start?

I'm really not sure how best to use the abacus to solve this type of problem.  Any suggestions would be most welcome!

1 comment:

  1. WOW very 'cheem'! Im very impressed that Ems is able to pick up the concept so quickly! She's a fast learner! Well done!