An slightly different, but I hope interesting resource for simple addition and subtraction of numbers up to 20 using robots/number machines. EXPLANATION POWERPOINT (24 slides) Initially: 4 worksheets with answers ALL the clip art I used to make the resource for you to use. use the clip art to make your own worksheets or large scale robots for lessons or displays Please note This resource is the beginnings of an idea. It is as uploaded and as yet UNTESTED with a class. It has been designed to mak