Tuesday, March 04, 2008

Teaching Ideas #3

Addition Through 20

There are a few tricks that are helpful when teaching addition to 20. Here are a few that helped all my children.

*When adding 9’s to a number up to 10, go back one from that number and say “teen”.

Example: 9 + 4 (go back one number --say "three-teen", or 13"


*When adding 8’s to a number up to 10, go back two from that number and say “teen”.

Example: 8 + 6 (go back to 5, go back to 4, say "four-teen", 14)

*Memorize the doubles

*Learn “doubles plus one” (ex. 6 + 7 is the same as 6 + 6 + 1)

Start slow, work on one trick at a time and master it before moving on to another. Soon, your child will have addition up to 20 memorized.

Have any additional tricks for addition through 20?

11 comments:

Patrick Sievert said...

three words: fingers and toes.

Cindy Beall said...

Now that is great. Never ever thought of that. I usually just yell, "Memorize it, boy!"

I know. So encouraging, right?

jimmy paravane said...

well, here's a grandparent technique for better math. "keep trying sweety. I know you can get it because of course yer a mathematical genious. Go ahead and add it up for me again." (grin)

Roger Garrett said...

I have used all of these but it is funny how literally my son takes it and will apply the same rule to any equation that has a 9 in it. I taught him the multiplying by 9 short cut by taking one away and adding the number that gets you back to 9. 9x8= go back 1 to 7 and takes 2 to get to 9 so it is 72.
He of course had to remind me that with a 9 you take away 1 and add teen. Too funny

Aaron said...

i needed you as a teacher!

deleise said...

My kids always seem to learn math quicker with m and ms or skittles...

Donna said...

That looks great...I am going to try it with our younger ones. Thanks Robin.

Natalie Witcher said...

Thank you! jimmy made me think of what my mom would do!

Kim Heinecke said...

what time does school start? My kids will be there tomorrow. Hope you don't mind. :)

Robin Meadows said...

Thanks, all for your comments. Roger, I'll be posting those multiplication tricks soon. Good ones.

Let us know if you try the addition tricks and how they work for your children!

shanna said...

great tip!