Practice adding and subtracting within 20 using a Double 10-frame & number line. Represent a teen number using a number bond to solve a Mystery Math Mistake. Use Notice and Wonder with a marble game ...

Match fun story problems with the correct addition or subtraction expression. Join Mrs. Gray for number talk with the Counting Buddy Junior. Then get ready to match fun story problems with the correct ...

Hello, I'm Mr Firth, and I need your help today as we learn to add and subtract within ten. You can use lots of things to help you add and subtract. Counters, number lines and even your fingers. Let's ...

Karen C. Fuson, Diana Wearne, James C. Hiebert, Hanlie G. Murray, Pieter G. Human, Alwyn I. Olivier, Thomas P. Carpenter and Elizabeth Fennema Researchers from 4 projects with a problem-solving ...

Jackson Ryan was CNET's science editor, and a multiple award-winning one at that. Earlier, he'd been a scientist, but he realized he wasn't very happy sitting at a lab bench all day. Science writing, ...