If you have any questions, you are always welcome to contact us. We'll get back to you as soon as possible, withing 24 hours on weekdays.
Customer service
All questions about your order, return and delivery must be sent to our customer service team by e-mail at yourstore@yourdomain.com
Sale & Press
If you are interested in selling our products, need more information about our brand or wish to make a collaboration, please contact us at press@yourdomain.com
Help
If you have any questions, you are always welcome to contact us. We'll get back to you as soon as possible, withing 24 hours on weekdays.
Customer service
All questions about your order, return and delivery must be sent to our customer service team by e-mail at yourstore@yourdomain.com
Sale & Press
If you are interested in selling our products, need more information about our brand or wish to make a collaboration, please contact us at press@yourdomain.com
A funny, entertaining introduction to Ben Franklin and his many inventions, including the story of how he created the "magic square." A magic square is a box of nine numbers arranged so that any line of three numbers adds up to the same number, including on the diagonal! Teachers and kids will love finding out about this popular teaching tool that is still used in elementary schools today!
⚠️ WARNING (California Proposition 65):
This product may contain chemicals known to the State of California to cause cancer,
birth defects, or other reproductive harm.
<div class="dynamic-checkout__content" id="dynamic-checkout-cart" data-shopify="dynamic-checkout-cart"> <shopify-accelerated-checkout-cart wallet-configs="[{"supports_subs":true,"supports_def_opts":false,"name":"shop_pay","wallet_params":{"shopId":73758048501,"merchantName":"Ergodebooks","personalized":true}},{"supports_subs":false,"supports_def_opts":false,"name":"amazon_pay","wallet_params":{"checkoutLanguage":"en_US","ledgerCurrency":"USD","placement":"Cart","sandbox":false,"merchantId":"A1G1ZY975O1T6J","productType":"PayAndShip","design":"C0002"}},{"supports_subs":true,"supports_def_opts":false,"name":"paypal","wallet_params":{"shopId":73758048501,"countryCode":"US","merchantName":"Ergodebooks","phoneRequired":true,"companyRequired":false,"shippingType":"shipping","shopifyPaymentsEnabled":true,"hasManagedSellingPlanState":false,"requiresBillingAgreement":false,"merchantId":"L873BZSC9NMQS","sdkUrl":"https://www.paypal.com/sdk/js?components=buttons\u0026commit=false\u0026currency=USD\u0026locale=en_US\u0026client-id=AbasDhzlU0HbpiStJiN1KRJ_cNJJ7xYBip7JJoMO0GQpLi8ePNgdbLXkC7_KMeyTg8tnAKW4WKrh9qmf\u0026merchant-id=L873BZSC9NMQS\u0026intent=authorize"}}]" access-token="c0f52a66b386e9fa5c0ab4c2febc737c" buyer-country="US" buyer-locale="en" buyer-currency="USD" shop-id="73758048501" cart-id="238e85cb835993b079e3b6b63331e8ce" enabled-flags="["d6d12da0","32a68cd0","a1c7ccbe","ce346acf","c0874428"]" > <div class="wallet-button-wrapper"> <ul class='wallet-cart-grid wallet-cart-grid--skeleton' role="list" data-shopify-buttoncontainer="true"> <li data-testid='grid-cell' class='wallet-cart-button-container'><div class='wallet-cart-button wallet-cart-button__skeleton' role='button' disabled aria-hidden='true'> </div></li><li data-testid='grid-cell' class='wallet-cart-button-container'><div class='wallet-cart-button wallet-cart-button__skeleton' role='button' disabled aria-hidden='true'> </div></li><li data-testid='grid-cell' class='wallet-cart-button-container'><div class='wallet-cart-button wallet-cart-button__skeleton' role='button' disabled aria-hidden='true'> </div></li> </ul> </div> </shopify-accelerated-checkout-cart> <small id="shopify-buyer-consent" class="hidden" aria-hidden="true" data-consent-type="subscription"> One or more of the items in your cart is a recurring or deferred purchase. By continuing, I agree to the <span id="shopify-subscription-policy-button">cancellation policy</span> and authorize you to charge my payment method at the prices, frequency and dates listed on this page until my order is fulfilled or I cancel, if permitted. </small> </div>
Stay in the know
Subscribe to our newsletter and stay updated on latest offers, discounts and events near you.
For MAP (Minimum Advertised Price) violations and Intellectual Property (IP) or Trademark concerns, please contact:
support@ergodebooks.com
⚠️ California Proposition 65 Warning: Some products sold on this website may expose you to chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information, visit www.P65Warnings.ca.gov.
