For this activity they’ll practice number recognition and counting. Simply print or draw out a chart as pictured below and use a rekenrek (Amazon) and something to cover the numbers (Dollar Tree) and they’ll be on they’re way to mastering teen numbers 
A rekenrek is an educational tool used in Mathematics instruction. It is a counting device with two parallel rows of beads (usually 10 per row). The beads are organized in groups of 5, making this a very useful tool in teaching number sense, counting, addition and subtraction concepts.
You can purchase a rekenrek on Amazon.
Anything may be used to cover the numbers, visit your local dollar store for foam blocks similar to the image below.
A Village Learning Center 