This interactive clock manipulative reinforces students' knowledge and understanding of telling time. As students move the hour, minute, and second hands on the clock, the time is shown in digital and analog form. The manipulative can be used for solving problems involving addition and subtraction of time intervals.

In this interactive demonstration, students select one of 6 array displays to illustrate 12 buttons. This virtual manipulative can help students to illustrate, represent, and explain multiplication and division problems.

This interactive virtual manipulative allows students to practice illustrating, representing, and explaining multiplication and division problems, as well as finding the area of a rectangle but moving rows and columns to visualize arrays.

This interactive/virtual manipulative provides base ten blocks that consist of individual "cubes," "rods," "flats," and "thousands-cube" (ten of each set for base 10). The activity reinforces students' knowledge of thousands, hundreds, tens, and ones. Students can either enter a number and see the visual representation, or they can create a number by selecting the appropriate base ten blocks. As students add or remove base 10 blocks, they can see the numbers increase or decrease to determine if they are on the right track.

This interactive resource defines the term "Bridging to Ten", and contains an interactive to illustrate the definition. Students use the place value visuals to illustrate bridging to ten, practicing building up to ten or building down to ten to more easily add two numbers.

This interactive demonstration resource defines the term "Fraction" and contains an animation and an interactive to illustrate the definition. Students can enter examples representing part of a set of items or part of a whole.

In this video lesson demonstration, a teacher uses dot plates as a strategy to assist children to subitize and name familiar arrangements of 1-5 dots. Children compare quantities and express a given number in two parts using fingers and dots. The teacher reflects on the lesson and provides strategies for teaching these concepts.