You can purchase additional learning kits for your student status only after you have purchased your student status; you can only purchase a learning kit once per student status. Learning Kit is really a game of probability. You need to spend the same IOTX as your student status to buy a learning kit with up to 3 times the mining output. There are 5 stalls here. They are 1 times, 1.5 times, 2 times, 2.5 times and 3 times respectively. The magnification is randomized. It depends on your luck. If you win 2x, you have no additional mining output. If it's higher than 2x, you've earned it. Below 2 times, you are not worth.