Walgreens has Crest Toothpaste for $3.29. Buy 3 and use the $5 off 3 Crest digital coupon. You get $5 in Walgreens cash when you buy 3, to make it free.

Walgreens has Crest Kids Cavity Protection Toothpastes, 4.2 oz, on sale for $3 each. Use the $2.00/1 Crest or Oral-B digital coupon.
You get $4 in Walgreens cash when you buy 2, making them free.

Walgreens has Colgate Optic White Toothpastes for $3.99. Use the $4 off 2 Colgate digital coupon and get $4 in Walgreens cash when you buy 2 to make it free.

purchase a box of Cure Hydration at your local Walgreens and submit your receipt to get 100% of the purchase price back.