The Siege of Orleans (1428-1429) during the Hundred Years' War between France and England is described, including the role of Joan of Arc.

The Common Core standard is that students understand that the numbers 100, 200, etc. represent so many groups of 100.

Video games often dole out points in groups of 25, 50 and 100 because they are easy numbers to multiply. Practice with patterns of 5 and 10 apply directly to understanding patterns with 50 and 100.

Second graders will extend their understanding of hundreds, tens and ones using dollars, dimes and pennies as another way to express groups of 100, 10 and 1.