Bake me a cake as fast as you can. Roll it, pat it, mark it with a TEN. Today we're helping out at a bakery and people are buying so many baked goods! In this lesson, we learn to subtract by groups of ten. Using a place value chart, students subtract larger numbers by focusing on the tens place and taking groups of ten away. It looks like I bought too many croissants: 10, 20, 30... uh-oh.