Draw a line on the board to represent a hill. Write the number zero at the left base of the hill and a number 10 at the right base. Write the number five at the top. Mark the numbers one to four on the left side of the hill, and the numbers six to nine on the right. Ask the child to choose a number from one to nine. Place a toy car on the board and 'drive' it to the number he has chosen. Discuss what will happen if you forget to put the car in park; depending on the number the car has reached, it will roll backward or forward down the hill and stop at the base. For example, if it has reached number 3 it will roll back down the hill and stop at zero. If it has reached the top of the hill at number 5 or more it will roll down the front of the hill and stop at number 10. This visual lesson reinforces the principle that numbers 1 through 4 round down, and numbers 5 through 9 round up.
This game is for a group of 10 children. Give each child a piece of paper with a number written on it and have her tape it to the front of her shirt. Assign numbers in increments of 10, from 10 to 100. Have the children stand in a circle. The teacher throws a ball to a player. After she has caught the ball the teacher gives her a number between one and 100 telling her to round it to the nearest 10. The child will decide on her answer and throw the ball to the child who is wearing that number. The teacher calls out another number to the player now holding the ball and play continues.
Choose three pupils to represent the number places. Give each of them a paper cone-shaped hat labeled with the letter H, T or U and a simple musical instrument such as a drum or shaker. Have the child in the hat labeled H slowly bang or shake his instrument any number of times he chooses between zero and nine. Have the rest of class count the number of bangs or shakes and write down that number on the player's hat; if the player wearing the H hat bangs his drum three times, the class writes three in the hundreds place. Continue in the same way with the other two players. Then do another round for the tens place and a last round for the ones place. Write the whole three-digit number on the board so the children can see if they have written it correctly, then say it together.
Call out a three-digit number; class members must organize themselves to make the number called by lining up in the correct place positions from left to right. Any players not needed should sit on the floor.