It’s easy to fall into the trip with trying to use the latest technology in the classroom. But, I think it’s better to begin with a specific need, and then find the best tool that meets that need.
In other words, rather than saying “what can I do with these iPads,” it’s better to ask “what will help my students to __.”
Multiplying By Decimals
In this example, I want students to develop curiosity about multiplying by decimals.
At this point, they don’t know how to do the calculation. And I don’t want them to get bogged down in the steps. Instead, I want them to see the big picture and ask interesting questions.
The perfect tool for this is a plain old calculator. It will handle the calculations for them, so their minds are freed up to see beyond the numbers.
Bonuses: no need to check out iPads, deal with software, worry about wifi, or avoid district internet filters.
One To Many
No need to give a calculator to every student. In this exploration, we want kids sharing their tools.
This sets up discussion and conflict. I’d recommend one calculator per group of three students.
Yes, instead of some pipe-dream of 1:1 iPads, we’re only need a single goofy calculator for every three students.
Don’t use more technology than is necessary!
Set Up A Pattern
Give groups a set of problems which will create an interesting pattern. Set the stage for students to make some (secretly) planned discoveries.
Remember, students do not know how to multiply with decimals by hand yet. They’re just using their calculators and looking for patterns.
- 8 × 3 = ___
- 8 × 2 = ___
- 8 × 1 = ___
- 8 × 0.5 = ___
- 8 × 0.25 = ___
If you ask them to look for patterns, your students may notice things like:
- multiplying by smaller numbers makes a smaller product
- multiplying by a decimal gives a product less than the original number
- sometimes multiplying by a decimal results in a decimal, and sometimes it doesn’t
This is interesting thinking!
The Roaming Helper
Your job during this time isn’t to instruct. Instead, you’ll roam around, troubleshooting, encouraging, and even confusing (yes, you can be a meddler in the middle)!
- Troubleshoot: Help kids solve their issues with the calculators or group members.
- Encourage: Congratulate them on spotting even the simplest patterns. Celebrate their mathematical discoveries. Most kids never get to figure it out in math.
- Confuse: Do they think they see a pattern? Add some complexity by recommending new numbers. Push them past simple understandings!
When kids make a discovery on their own, there’s a natural pull to keep going. Your students might want to explore beyond the minimum!
Let them try many different decimals. Multiply by: 0.1, 0.01, 0.001. Try: 0.9, 0.99 0.999. What patterns do they see?
If you’re lucky, groups might even ask about dividing by decimals! Or what if we multiply a decimal by a decimal? Even a simple calculator can handle these operations, so let them go for it (feel free to demonstrate calculator use as needed).
Let your students experiment and explore. They’re getting a feel for the numbers before getting their hands dirty with the algorithm.
The Big Chat
Save time at the end for a whole group discussion about their discoveries. Let them do the talking and explaining. Say things like:
- Did anyone else see that?
- Jane, did your group find anything different (you know they did because you checked in on them)?
- What do you think would happen if… (especially great if a group tried this already)?
- Anyone disagree with this pattern? Do we need to add something?
- Can we summarize these findings in five words?
I’ve used calculators to play with exponents, percents, and adding negatives, but I’m sure you can come up with even more uses for the plain-old calculator.
Let me know what you come up with!
Free Math Project Ideas
I'll email you a new math project idea every couple of weeks!! Get some math projects!