Warm up your brain
Get into the maths mood get your children to tell you some quick fire one more and one less questions. What is one more than 3? What is one less than 2? You may need to show this on your fingers and get your child to copy you. (if your child is struggling with this then keep on this for today and use objects and number lines to do it).
Pick and number and ask your child to pick a number (0-5 or 0-10). You take than many objects and your child takes the number of objects they said (pasta, rice, spoons or anything). Ask who has more and who has less (this could be the end point and just repeat this activity with different numbers).
Explain what 'the difference' is and model counting on from the smaller number. Line them up if you need to compare them. How many more does the bigger number have? Not how many you have but how many extra do you have. Model saying "I have 3 more than you and you have 3 less than me. The difference between 2 and 5 is 3". Or however yours works out. Repeat this for different numbers. Complete the worksheet after. You don't need to write on it, just talk through it or write your answers on a different sheet of paper.
If your child doesn't understand find the difference then go through the PowerPoint slides below.