Addition of three plus other numbers quiz online for children in kindergarten, 1st, 2nd and 3rd grades. Children will have the freedom to review basic addition skills at their convenience either at home or in school. Parents and teachers will also find this useful as a review tool. This online test is an educational quiz which can be taken either on any mobile device or on a PC. As you take the test, feedback will be collected in the end and a score is displayed as well. Keep trying until you gain a full mastery of this math skill.