These Chalk It Up. Hearts Hot Spots Stickers are perfect for encouraging and rewarding students who give their best efforts. The charming chalk heart design makes these incentive stickers great for use all year long, and especially during February or on Valentine's Day. Use these mini motivational stickers with our classroom incentive charts and individual student incentive charts. Each pack includes 880 stickers. Stickers measure approximately 0.5" . Coordinates with other Chalk It Up. products.