We used foam plates divided into 3 sections (plastic would work too) for practice taking the groups of tens and the group of ones and putting them together to make expanded form. I kids loved this activity and it made the concept a lot more visual and understandable for them. We practice putting the manipulatives on each side first, then we practiced just drawing them. The left side is for tens and right side is for ones.
10. We played a fun dice game with partners called Roll it! Make it! Expand it! This is a great Freebie from [Teaching 1st]. This was perfect for giving more practice to our newly acquired knowledge of expanded form.