Promote a deeper understanding of adding up to two 4-digit numbers with this Year 4 Add up to Two 4-Digit Numbers (Practical) Discussion Problem. Two questions challenge children to use what they know about adding 4-digits with 1 exchange to help them come up with possible answers. Both questions require logical thinking and a good understanding of 1 exchange. The resource also comes with an answer sheet to help with marking. Use this resource as an extension activity either in small groups or pairs. Try it today!