Content: Science Quiz On Mixtures For Kids Online. This quiz will enable students in 1st, 2nd and 3rd grades to learn to distinguish between mixtures and non-mixtures. There are simple and compound mixtures. There are also items that are composed of a single element e.g. a gold ring is not a mixture, but a cup of coke is a mixture given that it is composed of other compound mixed together. After taking this test, students will expand their understanding of substances that are or are not mixtures. This is an interactive online quiz for self-study and for homework. Feedback is instant as students take the test.