# Conics Hide and Seek

We just wrapped up our study of conic sections, which can be a pretty dry topic. So to liven things up, I had my precalculus students go on a scavenger hunt. These days, everyone has either a digital camera or phone with a camera, so everybody could participate. Here is the handout I gave them outlining the rules:

Conics Hide and Seek

Names____________________________________

Math is all around us, and in this activity, you are going to find some places where it is hiding. We have finished our study of conic sections (parabolas, circles, ellipses, and hyperbolas), so it’s time to have a scavenger hunt! Using your phone or digital camera, you and a partner will explore the campus and take a picture of at least one example of each type of conic. The team with the most points will get a prize. You are on your honor not to share your finds with other teams.

Here’s how many points each type of conic is worth:

Circle: 1 pt (maximum of 5 examples)

Ellipse: 2 pts

Parabola: 3 pts (remember, a parabola is not the same as a “U”!)

Hyperbola: 5 pts

You can submit your photos via email. Happy hunting!

They spent more than half of an 80-minute block combing the campus for examples of conics. Did this activity involve rigorous mathematics? No, but it was a lot of fun for the girls, and it opened their eyes to some of the ways math can describe the world around them. When we reviewed the teams’ submissions, there was a lot of discussion about whether certain shapes actually were parabolic, or ellipsoid, etc. All in all, a very useful activity.

Here is a sampler of the best submissions. The winning team took over 100 photos!

I’ve been using Twitter more and more the past few months, picking up great ideas from other teachers and bloggers. Now I’m considering applications of it with my students. It would make a nice back-channel communication method for students who would like to comment on something without resorting to email. By creating hashtags for my courses, we can all have running conversations on a variety of topics. To encourage that, I’ve embedded a Twitter feed into my courses’ Moodle pages:

Now they can see the tweets my “fractad” feed is getting, as well as send a quick tweet directly to me.

Here are the steps involved in making your very own Twitter feed you can embed in your Moodle, Haiku, or Blackboard page:

2. Choose “Settings”.

3. In the menu on the left, choose “Widgets”

4. Click the “Create New” button, and select the various settings for your widget.

5. Click the “Create Widget” button, and copy the html code that will appear. Use this code to embed the widget into your LMS page.

One thing that’s very cool – you can create a Twitter feed for any Twitter user. If your school has an account, you can embed that feed into your page. Or, you might want to embed the feed of a professional organization you follow (NCTM, in my case).

If you’re relatively new to Twitter, and you aren’t sure who or what to follow, here’s a list of people and organizations that I’ve found to be very useful:

Math & Science:

@lostinrecursion (Paul Salomon)                             @rmbyrne (Richard Byrne)

@MT_at_NCTM (NCTM Mathematics Teacher)       @Mathalicious

@fnoschese (Frank Noschese, science)                  @ddmeyer (Dan Meyer, math)

@desmos                                                                   @mrbarlow (science)

Education:

@Socrative                    @Edudemic

@ASCD                        @KindleTeacher (Meg Griswold, English)

@edutopia                    @kindleworld (Andrys Basten – lots of Kindle tips)

@PatBassett (Former NAIS president)

(Chrome users: don’t forget to install the Notifier for Twitter app!)

Update: I just showed my calculus students the feed on their Moodle page, and they were incredibly excited. I’m already getting lots of interaction with them!

# Vectors and Dancing – A Dangerous Mix

I came across this activity from Jim Noble at www.teachmaths-inthinking.co.uk the other day and tried it out with my precalculus class. We defined four different dance steps with vectors, and combined them into a routine.

We then tried out the routine while listening to Donna Summers’ “Hot Stuff”. As you can see, we could have spent a little more time practicing!

I liked this activity, because it got girls up and moving. We had a good discussion of the various ways to combine the steps to reach the same destination, and they mapped them out using the vector definitions. Jim Noble has made available some excellent worksheets that go along with this project.

If you’re trying to teach simple vector addition and scalar multiplication give this activity a try!

# A Nice Game That Illustrates Vector Addition

NCTM (National Council of Teachers of Mathematics) has a very clever online game that helps students understand vectors. I introduced it to my precalculus students today, and they spent more than 30 minutes completely absorbed in it.

The game involves determining the correct velocity vector for a boat to accomplish several tasks. There is a vector for the water’s current, and you can also have the resultant vector displayed. Here’s a screenshot:

Players can adjust the boat’s velocity vector, as well as the water current’s vector. After some trial and error, my students eventually realized that simply pointing the boat’s vector towards the island won’t work, and they began to add the two vectors at the boat’s bow to get a better idea of where it would end up.

There are several levels of the game, and after playing with it, my students all agreed that they had better understanding of what is involved in vector addition.

Here’s a short video of what it looks like to play: