Two Truths and a Lie variations.

Two truths and a lie is a great activity where three statements are made.  Of those three statements, one is a lie while the other two are truths and the person reading it must decide.  Often times the lies are not that easy to determine.  


If you look at the picture of the bell peppers, I could say:

1.  The peppers are arranged so there are four rows of four and one row of two.

2.  One - ninth of the green peppers have some red.

3. Two - ninths of the peppers are yellow.

Which one is the lie?  If you aren't sure it's the middle one because there are only 14 green peppers and two of them are red so the fraction should be one - seventh.  The one - ninth is based on counting all the peppers, not just the green peppers.

When using photos or diagrams, people have to think hard about how the written apply to the visual and determine if the interpretations are correct.  It can spark lots of discussion among students which helps increase their understanding and mathematical vocabulary.  In addition, the teacher can place a photo on the board or in google classroom so students can create their own two truths and a lie.  Once students have finished creating their two truths and a lie, place them up around the room and let students check out each one.  You could even have students work their way through each other's creations.

If you want to use an already created two truths and a lie as part of the unit, Desmos has four already made.  They deal with lines, parabolas, conic sections and exponentials.  The activities have a graph and ask the student to select the lie and justify their choice.  All four are set up so you can add one or the students can add their own.

Another possibility is to select a graph without any information on it, create two truths and a lie for it and then have the students determine the lie.

I might come up with something like this for this graph.

1.  The graphs shows a repeated pattern of a decrease, gentle increase followed by a sharp increase in the purchase of chocolate.

2.  The graph shows a car hitting the breaks, starting to speed up, stomping on the gas petal before slamming the breaks to stop, starting again and speeding up rapidly.


3.  A person is walking back from the store, they climb a hill for a bit, then begin to go down a slight hill before going down a steep hill rather quickly, then they start doing up a hill again, before starting down a hill and finally running down a hill.

You can also give each student the same picture so they can create their own.  I'm going to let you figure out which one is the lie.

Let me know what you think, I'd love to hear.  have a great day.