Four is very fast to do when you multiply by 2. Here's a little good advice: Please just always double twice!
The Best of Times gives kids an intuitive understanding of multiplication, encouraging them to arrive at answers on their own rather than memorizing the times tables. A child who can multiply by two, for instance, can multiply by four and even eight! Likewise, times six builds on times two and times three.
With his common-sense approach, Greg Tang encourages kids to solve problems creatively, building both their skills and their confidence.