The Blackboard #1 is a Wall Cover that serves as decoration and to raise a room's SLVL for Pixpets on Hoards.
How to Obtain
Blackboard #1's can be found inside Capsules obtained from hoards by pixpets with a matching color and WU range. Using a Decorative Item Potion and/or a Item Rarity Excluder of the appropriate grade can increase the chances of finding some.
Trivia
The info bubble says this is "Teaching about SLVL/LVL"
Origin
The Blackboard 1 was added to the site on Apr 4th, 2019.[1]