Cloud, Genesee, & Hamayan (2000). Dual language instruction: A handbook for enriched education. Boston, MA: Heinle & Heinle Publishers.
In a section entitled, "What should we do about code switching?" the authors suggest the following guiding consideration:
"Code switching may be misinterpreted as an incapacity to separate the two languages properly. This is rarely the case. Studies have shown that code switching by fluent bilinguals is rule-governed and is used in a highly controlled way. It is used to convey subtle meanings, to show identification with speakers of the other language, and to accommodate the listener. It is also used as an indicator of dual identity. Code switching is often evidence of linguistic creativity and sophistication, and it is no cause for alarm" (pp. 63-65).
The authors go on to proscribe the following warnings about allowing code switching in the classroom:
keep use of each language separate from the other, to clarify appropriate settings for each
until proficiency is attained, students may inappropriately rely on it for ease of communication, and not the above reasons