Here is a website that has an online quiz about comparing length and height http://www.ixl.com/math/grade-1/compare-objects-length-and-height This website is one that you can pay for if you want to keep track of your score, otherwise it can be used free of charge if you do not want to keep track of your score. Please note it is an American website so some measurement is not metric.
If you would like to continue our discussions about measurement at home you can weigh your child and talk about kg and compare the weights in the family. Making predictions about weight before stepping on the scales. Such as I think I am going to be 20 kg and I think my big sister is going to be 30 kg. Or you could measure your child's height and compare heights of different family members. Or you could do some cooking together where you read a recipe and look at the different measuring tools used in cooking.