Understanding place value is essential for developing a solid foundation of mathematical understanding. The Base 10 blocks are a great manipulative for visualizing and understanding place value for whole numbers and for decimal numbers. We have already created two digital activities/tools to practice modeling whole numbers with base 10 blocks. Number builder 4D and Number builder 6D. Number builder 4D uses (random) numbers up to 4 digits and number builder 6D uses numbers up to 6 digits. Today w