Ooooo. Scary! This is a slightly didactic activity on vampire bats. We've given lots of interesting metric and customary unit facts and asked students to relate those sizes to more familiar objects. Simply enjoy the season with this slightly creepy activity ... metric and customary units, size and weight comparisons, and blood-sucking bats.

# Water saving toilets

How much water is used? How much water could be saved?

The activity: PottyTime-SavingWater.pdf

CCSS: 5.MD.1, 5.NBT.7, 6.RP.3, 7.RP.3, MP2

# Ghost Whisperer

This Friday is the 13^{th}. Let the spooky stuff begin!

Students can play this game online at Ghost Whisperer Crystal Ball and

- Figure out why it works.
- Construct viable arguments
- Critique the work of others

This activity can be used with any grade level elementary through high school. Younger students might work with patterns, multiples and order of operations. Older students might work with systems of equations to prove how the Ghost Whisperer works.

# Immigration numbers

Here's an opportunity to work with calculating percents and the percent changes in the U.S. immigrant population. Students can reflect on what those changes demonstrate.

Start your class with this very cool movie showing the history of immigration in the U.S. You might play the movie twice and pause it repeatedly during the second showing.

from Max Galka, Metrocosm

# Columbus Day and navigating into the infinite-looking ocean

The Niña

Columbus Day is a bit of an enigma that used to be celebrated throughout all of the Americas. Columbus's mission and arrival are now thought to have not been as noble an endeavor in the way that indigenous people were treated by the European colonization that began with Columbus's voyage. Now, many states no longer celebrate Columbus Day.

This post is about imagining sailing off into the West, into an empty-looking ocean, to find what your captain believes is a good route to the Indian subcontinent. Sailing West was a huge navigational feat. Fortunately Columbus's ships experienced good weather but they landed in the Caribbean ... not southern Asia.

Use some of what we know now about navigation to examine this trek and do some reasoning and experimentation with the data.

# Uh oh! Am I going to run out of data?

Let your students consider the graphic first individually and then in groups of your choosing before handing out the activity sheet. This might be an excellent beginnng-of-the-year, get-to-know-each-other task!

The activity: DataRemaining.pdf

CCSS: 6.RP.A, 7.RP.A, MP4