Students need opportunities to work with many and varied representations of concepts. Virtual manipulatives are digital objects that resemble physical objects such as place value blocks. As their name implies, these objects can be “manipulated”; for example, they can be moved, rotated, broken apart, or combined. The dynamic nature of these digital objects makes them an excellent resource for enhancing teaching and learning.
Teachers and students can interact with virtual manipulatives in ways that are not always possible with concrete materials. Working with virtual manipulatives can also be faster than working with concrete materials, making it possible to explore a greater range of examples. For example, a student using virtual place value blocks (see http://nlvm.usu.edu/en/nav/category_g_2_t_1.html - Base Blocks Addition) can see a tens rod broken into 10 ones when it is transferred from the tens column into the ones column. The student can then see the 10 ones rejoining to form a tens rod when 10 cubes are moved to the tens column. This is much more efficient than, for example, grouping and ungrouping 10 multilink cubes.
ELL students can use virtual manipulatives to demonstrate their understanding because language barriers are reduced. The teacher can verbalise what a student is doing, helping the student to make connections between concepts, actions, and language.
Using virtual manipulatives on an interactive whiteboard is a useful way to make student thinking visible. Other students can be drawn into discussions about what a student has done and why, easing the way for students to participate in mathematical discourse.
Virtual manipulatives are not, however, a total substitute for concrete materials. For example, students should be familiar with place value blocks before being introduced to a digital version of them, particularly students who find it difficult to interpret two-dimensional representations of three-dimensional shapes. Teachers should support students as they work with virtual manipulatives, ensuring that they make connections between the manipulatives and the concepts they embody.
Students who have been working with concrete or virtual materials in ALiM sessions can use virtual manipulatives at home to consolidate their learning.
For a list of websites providing virtual manipulatives, see www.cited.org/index.aspx?page_id=151#resources