Simple Strategy to use for Common Mistake: Counting by Tens and Ones

My kids sometimes continue counting by tens even when the unit has changed to ones. For example, there are six dimes and seven pennies. My students begin counting correctly, "10, 20, 30, 40, 50, 60..." but then instead of adding the additional ONES, they continue counting "70, 80, 90, ...." giving them the incorrect answer. I tried the simplest strategy that has really worked for my kids. They clap when the unit changes! So, now, they pay more attention to when the unit changes so they can loudly clap. I can't believe it works but it has really helped some of my students that were doing this frequently.