Statistics doesn't have to be scary. In fact, I found that my students loved learning stats because we did so in the absence of difficult computation. It was always a pleasure to see who would surprise me.
The "Big 5" in stats are as follows: Minimum, Q1 (the first quartile, the 25% mark, Q2 (median), Q3 (the third quartile, or the 75% mark), Maximum. From there you can solve for the range (max - min) and the almighty Interquartile Range (Q3 - Q1)
Depending on the class I allowed calculators, yet still required students to demonstrate what they calculated. This lesson does not include tricky numbers.
Step-by-step guide (odd and even data set; use this as the minilesson, I taught solving for the odd data set day one and the even set day 2 and assigned problems accordingly)
Guided Practice (works well in pairs, there are additional data sets provided for early finishers)
Homework (double sided, I assigned this over two evenings to spot check for issues, odd data sets the first night, even data sets the second)