The Place Value Village
With this visual aid, I teach the concept of borrowing, carrying and place value. We practice writing large numbers and teach how to read them. Each "house" is named after a place value: the Ones House, Tens House, and the Hundreds House. Each group of three houses is on a "street": Ones Street, Thousands Street, Millions Street and Billions Street.
Each street is separated by a comma and there's a decimal point to the right of the last house.
I attached the houses to a white board, so the kids could practice below and erase easily. After nearly 10 years, the construction paper had faded and the cardstock looks a little the worse for wear, but it's still serviceable! This is by far one of the best tools I ever made to use for math!