One Million Heartbeats!!

How many times does your heart beat?

Is it beating at this moment??

How long do you think it would take to have One Million Heartbeats??

This is an activity I have done a number of times across the years, and it always seems to get the kids excited about finding the answer.

Rather than just posing the question at the start of the lesson, I usually go outside and play a game with the class and really get the blood pumping!

While having a stretch afterwards, I will casually ask them if they can feel their heartbeat, and where do we find it on our bodies.

This initiates a lot of discussion, so I suggest that we all count our heartbeats for 1 minute (or sometimes for just 15 seconds - more about that later).

"Remember your score and write it down when we go back inside" , or sometimes I'll quickly write it down where we are.

This is when I put the challenge to them.

"Now that you know how many heartbeats you have in one minute, how long do you think it would take to have 1 000 000 heartbeats?"

First of all, let’s find our heartbeat again.

Where is it easiest to locate for you?

Heartbeats are usually measured per minute. How many beats in one minute for you?

Do we need to measure for an entire minute? How could we make it easier?

Now, using your information for 1 minute, work out the number of beats for larger time durations…

• 2 minutes

• 5 minutes

• 10 minutes

• 1 hour

• 12 hours

• 24 hours

• 2 days

• 1 week etc

As you start to get closer to 1 000 000, look back through your amounts and choose which ones to add on, or multiply. Can you get the exact time it takes?????

Messy Maths

So often our kids are told to keep their work as tidy as possible, and I get that.

But, there are times when we can throw caution to the wind and make the emphasis the investigation, rather than the presentation.

In this activity I actually encourage the 'messiness'. There is lots of calculating to be done, so rather than worry about setting it out neatly, I let them do it wherever they like on their page, so that they get their results quickly.

There can be lots of scribbling and quick calculations all over the page!

The only condition I put in is that they must be able to locate their results quickly.

This might mean putting a quick heading above their calculation saying 1 min, 5min, 1 hour etc

As they will need to keep coming back to their various calculations this is why I stress the importance of being able to locate different calculations quickly.

In this activity the results can be found by doing lots of repeated addition, and then some subtraction where needed.

This leads to the discussion about what can be done as an alternative to repeated addition?

It is also a great opportunity to conduct workshops and explicit teaching sessions on the processes of the 4 operations.

By doing them at the point of need, I find the students are more receptive, as there is a purpose and intent behind the reason to spend time explaining them in greater detail.

In trying to work out how long it takes for each of us to have 1 million heartbeats there is so much of the maths curriculum that can be covered, and it gives us great insights into where the students are at in terms of knowing which processes are best suited to solve a problem.

The same concept can be applied to other problems, and modified to suit different grade levels...

• Instead of 1 000 000 heartbeats, choose a range more suitable to that level. eg 500,

1 000, 5 000etc

• Instead of heartbeats, measure other things. How long would it take to click my fingers 1 000 times? How many steps a day would I take? (without using a device) How many hours/seconds/days old am I? How many breaths a day do I take? How long have I slept for in my life? etc

• Use the results to create graphs of different varieties. In this way they are gathering relevant information to graph rather than being given irrelevant data from a source which has no meaning to them.

I love doing this activity, and it is one where much of the enthusiasm to do it needs to come from the teacher, which is why I always include myself in the investigation.

My most recent experience with it in a Gr 3/4 class resulted in a number of children working out their 1 000 000 heartbeats down to the last second!!!

Good luck with this investigation, I hope it encourages you and your children to come up with even more!!