Audience Participation Post (for math teachers)

I switched jobs this year.

I'm still working with gifted kids, but I'm "pushing in" instead of "pulling (kids) out."
I'll admit, I was kinda skeptical and worried about how this would work.

There's a pretty steep learning curve some days.

And then, some days, you find an old email draft about trying some math website
and at the same time circumstances require you to teach the entire 3rd grade class
on your own so you figure, "What the heck, let's try that new website.
What's the worst that could happen?"
I mean, really, if it absolutely bombs, you throw on a Vi Hart video
(if you've never seen Vi Hart and you teach 3rd - 12th grade, go check her out
right now. Really. Right. Now.)

So I'm with this 3rd grade class that has a pretty wide range of abilities and I
tried this problem from the website Open Middle:

Directions: Use the numbers 0 – 9, no more than one time each,
to make the following problem true.

Jenny has ? ? ? marbles. Her brother has ? ? ? marbles.
Together they have ? ? ? marbles.

After a brief check to make sure everyone understood the problem,
we got out white boards and markers and started working. The kids naturally
gravitated into groups. There were SO MANY good discussions about math!
What did this problem mean? Where could you use a 0? What happens if
we add to a 4 - digit number? 

30 minutes. 

Eight and nine year olds laid on the carpet and worked for 30. Solid. Minutes. On
Math. No technology besides a white board and they didn't want to stop. It took 30
minutes before one group finally had an answer. I said that it was different than the
one I got, could they find more? 

The kids who couldn't find the right answer spent those 30 minutes building
their 3 - digit addition skills. That was the worst thing that happened. Really. 

The site has problems from many great math educators, and it's leveled by standard
k - 12. 

This was the coolest thing I'd experienced in the classroom in a long time.
The kids LOVED it. The gifted ones and the not-gifted ones, too. 

This is my first-ever audience participation request, but please --
if you teach math, just TRY one of these and if you want to, tell me what you think!
I'd love to hear.

Happy Math-ing!