The "wh" sound

This week in The Learning Den we are working on h digraph spelling patterns.

When we looked at the "wh" pattern we discovered that most of the words we use to ask a question begin with "wh". Take a look at this song to see what we mean! 

"Wh" usually makes the "w" sound but can you spot which word beginning with "wh" actually makes the "h" sound?
At the end of this "wh" song (you will have to be quick to keep up!) the last word is "calculus". Can you find out what calculus means?