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Receive FREE SHIPPING on orders over $99 placed on the Didax website and shipped within the contiguous US. No promo code is required to receive this offer.
The order total for free shipping is calculated after any discounts are applied. Orders containing Eureka Math Kits DO NOT qualify for free shipping.
Free shipping valid ONLY on orders placed on the Didax website shipped within the contiguous US. Our regular shipping policies applies to other orders.
Need new ideas? Looking for quick tips for teaching tricky concepts or organizing your math centers? Class Ideas is your go-to spot for inspiration, information and innovation and it’s an ideal way to stay current with the latest trends in math teaching and learning.
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Double, or dual, number lines are an ideal "visual model" for solving mathematical problems involving equivalences, ratios, proportions, and more. Though double number lines are not mentioned specifically in the CCSS until Grade 6 (6.RP.3), they are a viable tool for mathematical understanding beginning as early as first grade.
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