Learning - students considered that the practice tool had a positive effect on their learning.

Spacing Algorithm - students considered it useful.

Spacing Feature - "More importantly, as opposed to previous studies that report students’ dislike of the desirable difficulties, many students in our study found our design of spacing helpful "

Interleaving Feature - Students liked this feature, the versatility of the questions.

Schedule Visualization - Some students liked, some didn't remember this feature at all.

Progress Tracker - Students considered it useful and motivating.

Other Practice Tools - Students preferred this practice tool over the Problem Roulett.