11. A computing system comprising: a keyword store hosted on one or more server computers comprising non-transitory machine-readable storage media, the keyword store configured to store one or more words of text of one or more resources; and at least one processor of at least one computer configured to: determine a level score of a learner based upon a plurality of responsive inputs received from a client device associated with the learner via one or more networks; determine a pedagogical value threshold based upon a level score of the learner and a resource difficulty score of a resource; identify in the text of the resource each word having a word difficulty score satisfying the pedagogical value threshold; store into the keyword store each word satisfying the pedagogical value threshold; select from a resource store the resource comprising content associated with one or more learner attributes of the learner using each word satisfying the pedagogical value threshold; identify a type of learning activity that exercises a language skill for improvement of the learner and corresponds to a goal of the learner; identify one or more records in a distractor store containing a set of one or more distractors of a type suited to the identified type of learning activity; and generate a learning activity of the identified type of learning activity utilizing at least one of the set of one or more distractors extracted from the selected resource.
11. A computing system comprising: a keyword store hosted on one or more server computers comprising non-transitory machine-readable storage media, the keyword store configured to store one or more words of text of one or more resources; and at least one processor of at least one computer configured to: determine a level score of a learner based upon a plurality of responsive inputs received from a client device associated with the learner via one or more networks; determine a pedagogical value threshold based upon a level score of the learner and a resource difficulty score of a resource; identify in the text of the resource each word having a word difficulty score satisfying the pedagogical value threshold; store into the keyword store each word satisfying the pedagogical value threshold; select from a resource store the resource comprising content associated with one or more learner attributes of the learner using each word satisfying the pedagogical value threshold; identify a type of learning activity that exercises a language skill for improvement of the learner and corresponds to a goal of the learner; identify one or more records in a distractor store containing a set of one or more distractors of a type suited to the identified type of learning activity; and generate a learning activity of the identified type of learning activity utilizing at least one of the set of one or more distractors extracted from the selected resource. 14. The system according to claim 11 , further comprising hosted on one or more server computers comprising non-transitory machine-readable storage media, at least one data store of the one or more data stores configured to store a record of the learner, the record containing the level score of the learner.