My daughter can tell time. She understands that a minute is 60 seconds and 60 minutes make up an hour but she does not understand exactly what waiting for a minute to pass can feel like. I bought her these sand timers to help her understand exactly the amount of time that makes up minutes and how long it takes for a certain amount of time to elapse. The package came with 8 timers in 20 seconds, 30 seconds, 1 minute, 2 minutes, 3 minutes, 4 minutes, 5 minutes and 10 minutes. The timers come in different colors with coordinating colors of sand except the black and purple timers which came with white sand.
Each timer is about 3 inches tall and 1 inch wide so they are extremely easy to take along with us when we are on the go. I use these timers with her while she is taking a test, brushing her teeth, while playing games and studying time management. The timers are exactly accurate and the sand flows smoothly. She loves her new timers.