Basic stats tutorials:
learn about statistics with R
Introduction to statistics
what a statistic is 
types of data 
samples & replicates 
transforming & recoding 
Basic statistics
averages 
mean 
proportion 
median 
mode 
maximum 
minimum 
quantile 
ranges 
standard deviations 
Graphs
scatterplot 
linegraph 
pie chart 
dotplot 
bargraph 
histogram 
cumulative plot 
Much more
Stats Use / Abuse