Toys R Us has a promotion for a free $10 gift card when you spend $40 or more on LEGO purchases. Print out the coupon sheet now and use it in store until 3/29. The LEGO coupon is found on the bottom left corner of the 3rd page.
You may be able to combine this deal with current sale items. LEGO Legends of Chima Eagles’ Castle (70011) is on sale this week for $22.49.