This resource provides illustrated definitions of common metric terms. This would be a good resource for teachers to use with a projector to show estimations and relationships between metric units. This site is a great way to integrate math and social studies by taking a look at some cool Native American geometric designs with your class. The accompanying text is basically an advertisement for an educational program. These relationships are extended to a fractional relationship lesson.
Illustrations are helpful.
Pattern block paper can be printed for student use. This site is a great place for teachers looking for lessons to explore attributes, logical patterns, numerical patterns, and others. Activities could be used effectively with a projector. Shockwave is required. Students work in small groups to create shape handbooks using connections from nature and daily life.