The next time there’s a bake sale, school supper, teacher appreciation day, or other foodish pleasure at your school, someone will leave a polyethylene container behind. Even an old one at a garage sale will work well (spend no more than 50 cents). Despite attempts of the school to return these, one one ever claims at least one. It is your duty to claim them and use them for salt trays. A container with a top is highly recommended.
I prefer salt to anything else to fill the tray to 1/2″. Sugar gets licked. Fine sprinkles of a single color are a second-best choice. Sand seems to attract more moisture than salt. Multicolored sprinkles are distracting. Regardless, change the salt every three months or so.
I have kids look at their word in one place in the classroom (a spelling word, sight word, or phonic pattern word), and then walk to the tray and write it slowly in the salt. If the word doesn’t show up well, I’ve put black construction paper or a dark mat under the tray to provide contrast.
