I'm sure that many eager learners of Serbian are often puzzled by the meaning of prefixes and suffixes which are added to verbs in our language. While English uses different tense aspects (progressive, perfective) and phrasal verbs to express the same meaning, we tend to express aspect at the lexical level - that's why numerous prefixes and suffixes!
I think it's useless to puzzle students by bombarding them with numerous prefixes with one verb stem e.g. izaći, ući, otići, prići, doći etc. especially in one lesson. I think it's more effective to introduce one prefix, with common meaning, applied to the verbs with which students are already familiar with.
That's why I'll introduce the prefix "do-" = similar to English 'to'
1. meaning towards someone or something, or some finishing phase
trčati (run) - dotrčati (run to)
Sima trči (Sima is running)
Sima je trčao (Sima was running)
Sima je dotrčao (Sima has run (to me or some place))
šetati (walk) - došetati (walk to)
Ja šetam (I am walking/I walk)
Ja sam šetala (I was walking)
Došetala sam se do parka (I've walked to the park)
Došetaću se do tebe. (I'll walk to your place)
2. meaning 'additional'
pisati (write) - dopisati (add to what you've written)
Pišem knjigu (I'm writing a book)
Pisao sam pismo. (I was writing a letter)
Dopisao sam komentar (I added a comment)
Dopisao sam još jednu rečenicu (I've written one more sentence)
zidati (build) - dozidati (build some more/build up)
Zidali smo kuću pet godina (we were/have been building the house for five years)
Dozidali smo jednu sobu (we built up one more room)
dati (give) - dodati (add)
Dali su nam tortu (they gave us a cake)
Dodali smo malo šećera(we added a little sugar)